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A Randomised Controlled Trial Evaluation of Bookstart+: A Book Gifting Intervention for Two-‐Year-‐Old Children
Liam O’Hare & Paul Connolly
December 2010
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A Randomised Controlled Trial Evaluation of Bookstart+: A Book Gifting Intervention for Two-‐Year-‐Old Children
Liam O’Hare & Paul Connolly
December 2010
Additional Contributors The following members of the research team also made significant contributions to the research upon which this report is based: Jacqueline Mullen.
How to Cite this Report Any citation of this report should use the following reference: O’Hare, L. & Connolly P. (2010) A Randomised Controlled Trial Evaluation of Bookstart+: A Book Gifting Intervention for Two-‐Year-‐Old Children, Belfast: Centre for Effective Education, Queen’s University Belfast. © Centre for Effective Education School of Education, Queen’s University Belfast, 69-‐71 University Street, Belfast BT7 1HL, Northern Ireland Ph: +44 (0)28 9097 5051|Fax: +44 (0)28 9097 5066| Email: cee@qub.ac.uk| Web: www.qub.ac.uk
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Contents
Executive Summary .................................................................................................................... 7 Acknowledgements ..................................................................................................................... 11 1. Introduction …………........………….............................................................................................. 13 2. Methodology ……….......…………................................................................................................ 17 3. Findings ……………............………………......................................................................................... 23 4. Summary and Conclusions …………........……………...................................................................... 27 References ............................…………........……………...................................................................... 29 Appendices ..……….............…………….............................................................................................. 31
A1. Research Instrument (Children) ................................................................................ 33 A2. Statistical Models ...................................................................................................... 41
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Executive Summary
Introduction Bookstart+ is a book-‐gifting intervention established by Booktrust. Booktrust is an independent charity that aims to inspire a love of books in children and their families. In partnership with a number of organisations they provide a series of interventions to achieve this aim, namely: The Bookstart programme (which comprises of three packs: Bookstart Bags gifted to babies; Bookstart+ gifted to toddlers; and Treasure Chest gifted to pre-‐school children); Booktime; Booked Up; and the Letterbox Club. Bookstart and Bookstart+ are chronologically ordered interventions both gifted by health visitors for Booktrust. Bookstart is gifted by the health visitor in the child’s first year and Bookstart+ is gifted at the two year visit. The Bookstart+ intervention has two key elements. The first is a pack of books and associated reading materials provided in a bag and presented by a health visitor on the standard visit to families with a two-‐year-‐old child. The second element is that the health visitor also provides a demonstration of the pack to encourage parents to share books, stories and rhymes with their two year old child. The Centre for Effective Education at Queen’s University Belfast was commissioned by Booktrust Northern Ireland to undertake a rigorous and independent evaluation of the effectiveness of the Bookstart+ book-‐gifting intervention as delivered in Northern Ireland.
Outcomes For the purposes of this present evaluation, an outcome is defined as a real and discernible change in attitudes and/or behaviour that has occurred as a direct result of taking part in the Bookstart+ intervention. The following outcomes were identified by Booktrust and formed the basis for this evaluation:
• An improvement in parental attitudes to reading and books • An improvement in parent attitudes to sharing and reading books with their child • An increase in family use of the library
Methodology The evaluation took the form of a randomised controlled trial involving 462 families (with a two-‐year-‐old child) from the client lists of 146 health visitors in four geographical areas of the north east of Northern Ireland. Each health visitor was assigned four families. The four families assigned to each health visitor were then randomly allocated to either the intervention or control groups. Each health visitor therefore had two control families and two intervention families. Overall, this resulted in 235
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intervention families and 227 control families being approached by their health visitor to take part in the trial. The intervention took place for three months between March 2010 and May 2010. Pre-‐testing was undertaken in March 2010 and the post-‐tests were conducted in May 2010. All of the pre-‐test data collection was conducted by the health visitors. Post-‐test data collection was carried out by post and then a follow up phone call by a member of the research team. In both cases, data collection involved a self-‐complete questionnaire. The final achieved sample for whom pre-‐test and post-‐test data were collected comprised 96 intervention and 107 control families. This relatively high level of attrition (43.7% of those initially approached) was not found to introduce any known bias into the trial however, with the final intervention and control groups remaining well matched on their mean pre-‐test scores and a number of other demographic characteristics. Three measures, corresponding to the three outcomes identified for the programme, were created from the items contained in the questionnaire and each measure wasfound to be reliable and valid. Alongside data on the main outcomes, parents in the intervention group were also asked questions about their use of the Bookstart+ packs at post-‐test. Statistical analysis of the data took the form of a series of multilevel models with parents (level one) clustered within health visitors (level two). The main focus for the analysis was the effect of the programme as a whole in relation to the three outcomes identified. However, and in addition, further exploratory analysis was conducted to test whether there was any evidence to suggest that the intervention may be more effective for those families: from differing socio-‐economic backgrounds; with differing levels of educational attainment; with differing numbers of other children in the household; and living in different geographic areas.
Findings Parents’ perceptions of Bookstart+ Overall, parents responded very favourably to receiving a Bookstart+ pack. Two thirds of parents (66%) stated that they had used the book frequently and nearly all of the remaining parents (33%) said that they had at least made some use of the books. Only a marginal number of parents (1%) stated that they had not made any use of the packs.1 In terms of the parents’ perceptions of the pack’s benefits, over half (55%) felt that receiving the Bookstart+ Pack had had a positive effect on their own behaviour. More specifically, a small proportion (7%) said that they were previously ‘unaware of the benefits of reading with babies/toddlers and the packs have encouraged me to read more frequently with our child/children’ and nearly half (48%) said that they were aware of the benefits but that receiving the Bookstart+ pack had led them to read more frequently with their children.
1 Some percentages might not sum to 100.0% due to rounding.
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Effects of Bookstart+ In relation to the three outcomes, the trial found evidence of a positive effect of Bookstart+ on parents' attitudes to reading and books (Cohen’s d = +.192, p=.034) and some potentially encouraging signs of a slight improvement in parental attitudes to their child reading, although this latter finding was not statistically significant and therefore cannot be reported as a reliable finding (d = +.085, p=.279). These effects were found to be similar in size to other, comparable low-‐intensity early literacy interventions delivered internationally. In relation to the effect on families’ use of the library there was evidence of a small negative effect in that those parents who received the Bookstart+ pack were subsequently slightly less likely to use their local libraries (d = -‐.160, p=.055). In the absence of a more longitudinal component to the present evaluation, however, it is not possible to determine whether this represented a short-‐term effect, in that the receipt of new books through the Bookstart+ intervention reduced the parents’ immediate need to visit a local library, or reflected a more sustained and longer-‐term effect. In relation to the further exploratory analysis, Bookstart+ was found to be having similar effects across all subgroups of parents. Thus, no evidence was found of any differences in the effects of the programme for parents: from differing socio-‐economic backgrounds; with differing levels of educational attainment; who had differing numbers of children; and/or who came from different geographical areas.
Recommendations The findings give rise to a number of specific recommendations:
1. Given the evidence presented in this report of the proven effectiveness of Bookstart+ on parental attitudes towards reading, Booktrust should be encouraged strongly to develop and expand the programme further.
2. In developing the intervention further, it would be beneficial for Booktrust to consider how a
greater emphasis could be placed on encouraging parents to read more with their children.
3. It is important that Booktrust explore further the reasons for the negative effect on library use among families that received the Bookstart+ pack and put into place strategies to mitigate this effect prior to rolling out the programme on a larger scale.
4. A further randomised controlled trial evaluation of the Bookstart+ intervention should be
undertaken, using a larger sample and possibly run on a UK-‐wide basis. Such a trial would allow for the development of more detailed and sensitive outcome measures and also a more comprehensive analysis of the potential mediating influences of a number of key contextual factors. The trial would also allow the effectiveness of the intervention to be tested should any further refinements to the programme be made in line with the recommendations above and, in relation to library use, could test the longer-‐term effects of the Pack if an appropriate longitudinal component is added.
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Acknowledgements This research was conducted in partnership with Booktrust Northern Ireland and Northern Health and Social Care Trust. The research team would like to acknowledge the guidance and support from Liz Canning from Booktrust, Karen Elwood within the Northern Health and Social Care Trust in Northern Ireland and Kim Aiken from Libraries NI. The research team is indebted to the Health Visitors in the Northern Health and Social Care Trust that took part in the research and the children and parents who participated in the study.
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1. Introduction
1.1 Background Bookstart+ is a book-‐gifting intervention established by Booktrust. Booktrust is an independent charity that aims to inspire a love of books in children and their families. In partnership with a number of organisations they provide a series of interventions to achieve this aim, namely: The Bookstart programme (which comprises three packs: Bookstart Bags gifted to babies; Bookstart+ gifted to toddlers; and Treasure Chest gifted to pre-‐school children); Booktime; Booked Up; and the Letterbox Club. Bookstart has also inspired many similar programmes internationally that vary in size and scope. Examples include: Bookstart Japan; Bookstart Korea; Bookstart Thailand; Bookstart in the Falkland Islands; Buchstart in Hamburg, Germany); APEI, Portugal; ‘Read to Me!’ Canada; ‘A Book is a Treasure’ in Malta; ‘123 Lis avec Moi’ in Ottawa Canada; ‘Boekenpret (Fun with Books)’ in the Netherlands; and Boekbabies in Belgium. The Centre for Effective Education at Queen’s University Belfast was commissioned by Booktrust Northern Ireland to undertake a rigorous and independent evaluation of the effectiveness of Bookstart+ book-‐gifting intervention.
1.2 The Bookstart+ Programme Bookstart and Bookstart+ are chronologically ordered interventions both gifted by health visitors for Booktrust. Bookstart is gifted by the health visitor in the first year and Bookstart+ is gifted at the two year visit. Both these programmes are book-‐gifting programmes designed to inspire a love of books in children and their families. The Bookstart+ intervention has two main elements. The first is a pack of books and associated reading materials provided in a bag and presented by a health visitor on their standard visit to families with a two-‐year-‐old child. The second is that the health visitor has been trained to provide a demonstration of the pack and how it can be used by parents to read with their two-‐year-‐old child. The Bookstart+ pack contains the following items:
• A bright coloured nylon satchel style bag with the Bookstart Bear logo • Two books • A colouring book • A pack of crayons (Crayola Mini Kids) • A 'Numbers are Fun!' bedroom frieze • A set of 'Bookplates' that comprise colourfully illustrated stickers for children to place in
their books, saying, 'This book belongs to .....' that seek to encourage children to build their own book collection
• A Bookstart Toddler Book Guide that includes a list of recommended books
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• A guide for parents entitled ‘More Things to do with books!’ which focuses on early language and listening skills
The health visitors have received training on how to gift the Bookstart+ pack and to conduct a short demonstration aimed at encouraging positive family reading attitudes and behaviours. The training consisted of a Booktrust co-‐ordinator attending all of the health visitor area meetings in the Northern Health and Social Care Trust and providing a 30 minute presentation followed by a question and answer session. All health visitors were also provided with an administration pack detailing how to gift the packs, and more background on the programme and the current research evaluation. Nearly all of the 146 health visitors participating in this present trial attended the session, with a few absentees due to sickness. However all health visitors subsequently received the administration pack as they were individually addressed to each of them. The key messages stressed in the Bookstart+ coordinator presentation are:
• To give the pack with a warm and sincere message that encourages parents to start sharing books, stories and rhymes more often with their child
• Open one of the books and give it to the child, so that the parent can see the child’s reaction • Deliver the following key messages:
o Children need stories, songs and rhymes as an essential part of their development and thus it is important for parents to include this in their everyday routine.
o It is very important for parents to start from as early an age as possible . o Sharing stories songs and rhymes helps parents build loving relationships and
everyone can join in, including fathers, brothers, sisters and grandparents. o Parents are to be encouraged to learn more tips and ideas from the Toddler Book
Guide book included in the pack. o It is helpful for the health visitor to include priming statements about the benefits of
books. For example, they are encouraged to say: 'When you share this book with your baby you will have a lot of fun together.' They are also asked to explain that priming statements like these can remain in people’s memories and can positively influence parents’ future attitudes and behaviours.
o Parents are to be encouraged to recognise that babies and toddlers enjoy lots of different kinds of books and thus should be encouraged to join the library. They are also encouraged to explain to parents that it is free to join the library and there are no fines on books taken out on children's tickets.
o Parents should also be informed of the times of the ‘Rhythm and Rhyme’ sessions for babies and toddlers at their local library.
1.3 Previous evaluations of Bookstart+ The original Bookstart pilot programme was gifted in Birmingham, England in 1992 to a group of three hundred six-‐ to nine-‐month-‐old children. Wade and Moore were commissioned to evaluate the original programme several times over the following years. Initially, they did this by interviewing librarians, health visitors and parents involved in the pilot programme as well as by analysing evaluation questionnaires that were included in the pilot packs (Wade & Moore, 1993). The study findings reported that both professionals and parents welcomed the packs and felt that a range of literacy behaviours were improved including library membership, book purchase and book club membership.
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Following this Wade and Moore (1998) conducted a quasi-‐experimental matched group study at five years (n=41) and found the intervention children to be significantly ahead of a matched group in a range of measures of literacy and numeracy and the effects found were found to be fairly large for English (d=.65) and for mathematics (d=.45). Again, benefits were identified in the performance of 43 children that had received the Bookstart pack, compared with a matched group of students who had not, in their National Scheme of Assessment and Testing Scores (SATS) at Key Stage 1 (Wade and Moore, 2000). The overall longitudinal picture from these evaluations was therefore very positive with the pilot study children being significantly ahead of their peers on a wide range of outcomes. Following this there have been several other observational, qualitative and quasi-‐experimental investigations of Bookstart over the years that have all reported observing positive outcomes for the children involved (Collins, Svensson, Mahony 2005; NCRCL 2001; Millard, 2002; Moore & Wade, 2003; Hines and Brooks, 2005; Hunn, 2007; Spratt & Philip, 2007). In addition, research has also shown some positive results for the international versions of Bookstart programmes listed earlier (Kovalik, 2010; Vanobbergena, Daemsa & Van Tilburg, 2009). In relation to this body of evidence, however, it is important to note that all of these evaluations relate to the effects of the Bookstart programme designed for health visitors to gift during their one-‐year visit (excluding the studies on international versions of Bookstart). To date, no evaluations exist of the follow-‐up Bookstart+ evaluation gifted during their two-‐year visit. Moreover, none of the evaluations to date has used an experimental design. This present evaluation is therefore the first evaluation of Bookstart+ and the first evaluation of any of Booktrust’s programmes to make use of a randomized controlled trial methodology.
1.4 The Wider Evidence Base on Reading Interventions It is worth locating the Bookstart+ intervention within the wider set of interventions that exist aimed at improving early literacy outcomes among young children. A recent review of effective beginning (non-‐remedial) reading programmes by Slavin, Lake, Chambers, Cheung, & Davis (2009) identified four main approaches:
• Reading Curricula, which is the use of alternative textbooks and manuals by teachers. These materials often prescribe particular activities for teachers to undertake with children in relation to their literacy. Examples include Open Court Reading and Reading Street.
• Instructional Technology, usually refers to reading programmes that use computers, video or individual assessments. Examples include Waterford, Phonics-‐Based Reading, and Writing to Read.
• Instructional Process Programmes, are designed to provide teachers with professional
development training on delivering a specific instructional method. Examples include cooperative learning and phonological awareness training.
• Combined Curriculum and Instructional Process Programmes, are simply a mixed-‐method
programme that provide teachers with an additional curriculum and professional training on how to deliver it. Examples include Success for All and Direct Instruction.
In their review, Slavin et al, analysed 63 experimental studies and found that these four approaches tended to have differing effects, on average, as detailed in Table 1. The effect sizes shown represent a standardized measure of the effects of an intervention that can be used to allow the effectiveness of differing interventions to be compared directly. Effect sizes generally range between 0 (meaning
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there is no effect at all) and +1 (meaning there is a very large effect) and -‐1 (a very large negative effect).1 Table 1. Main methods of intervention for beginning readers and their corresponding mean weighted effect sizes
Intervention Type Number of Studies Effect Size Reading Curricula
7 +0.12
Instructional Technology
13 +0.09
Instructional Process Programmes
17 +0.372
Combined Curricula and Instructional Process Programmes
23 +0.29
Source: Slavin et al. (2009) Book-‐gifting programmes such as Bookstart+ do not sit easily within any of these four categories identified by Slavin et al. However, it is possible to gain some sense of the size of the effects that can be expected from such a programme by looking in more detail at the findings of one of the trials covered in the Slavin et al. review of an intervention called ‘Little Books’ (Phillips, Norris, Mason, and Kerr, 1990). As they explain:
Little Books is an approach to early literacy in which specially written mini-‐books are read by teachers or parents to kindergarten children to build their language and print concept. A total of 18 classes in 12 schools, with 309 children, were randomly assigned to four treatment groups: Little Books at home only; Little Books in school only; Little Books in home and school; and control. Children were pre-‐ and post-‐tested on the Metropolitan Reading Readiness Test (MET), which assesses auditory memory, letter recognition, language, and listening skills. All three treatment groups gained more than controls on the MET. Effect sizes adjusted for pre-‐tests were +0.33 for the home/school version, +0.19 for school only, and +0.14 for home only. Averaging across the three variations, the mean effect size was +0.22.
Slavin, Lake, Chambers, Cheung & Davis (2009: 65) In this case Bookstart+ can be regarded as being most similar to the home version of the Little Books programme which has a corresponding effect size of +0.14. While the size of this effect is clearly smaller than those associated with some of the other approaches identified by Slavin et al. and summarized in Table 1, it is important to note that these larger effects have been gained with correspondingly much larger levels of investment in terms of time and resources. As such, an effect within the range of +.10 to +.20 for a low-‐intensity intervention such as Bookstart+ should be regarded as noteworthy in relative terms. Such comparisons and benchmarking of the potential effect sizes of a book-‐gifting intervention are important to bear in mind when interpreting the findings to be reported in this present trial.
1 An effect size of ‘+1.0’ can be interpreted as showing that the intervention is likely to lead to a one standard deviation improvement of the mean score of those children in the intervention group compared to the control group. Similarly, an effect size of, for example, ‘-‐0.5” can be interpreted as showing that the intervention will actually lead to a reduction on the mean scores of those in the intervention group of one half of a standard deviation compared to the control group. 2 Slavin et al. 2009 found particularly positive effects in specific types of ‘Instructional Process Programmes’ cooperative learning (ES=+0.46), phonics-‐focused professional development (ES=+0.43), and teaching of phonological awareness to kindergartners (ES=+0.22 at the end of first or second grades)
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2. Methodology This section outlines the methodology employed for the current trial and begins by describing the specific outcomes, as agreed with Booktrust, that were tested and that provide the focus for present evaluation. The section concludes with an explanation of the approach used to analyse the data.
2.1 Outcomes For the purposes of this present evaluation, an outcome is defined as a real and discernible change in attitudes and/or behaviour that has occurred as a direct result of receivingBookstart+. This study focused on three main outcomes which were felt to reflect the core aims and objective of the intervention. These were:
• An improvement in parental attitudes to reading and books • An improvement in parents’ attitudes to sharing and reading books with their child • An increase in family use of the library
2.2 Design The randomised controlled trial involved 462 families (with a two-‐year-‐old child) from the client lists of 146 health visitors in four geographical areas of the north east of Northern Ireland. Each health visitor was assigned four families. The four families assigned to each health visitor were then randomly allocated to intervention or control groups. As such each health visitor therefore had two control families and two intervention families. Overall, this resulted in 235 intervention families and 227 control families being selected and randomised and initially approached by their health visitor.
2.3 Procedure The intervention took place for three months between March 2010 and May 2010. Pre-‐testing was undertaken in March 2010 and the post-‐tests were conducted in May 2010. All pre-‐test data collection was conducted by the health visitors. Post-‐test data collection was carried out by mail and then a follow up phone call by a member of the research team. In both cases, a self-‐complete questionnaire was used and a full copy of which is provided in Appendix A1. As described in the previous section, the health visitors had received training on how to gift the Bookstart+ pack and conduct a short demonstration aimed at encouraging positive family reading attitudes and behaviours. It should be noted that many of the families in the evaluation (n=250; 73.3% of families in the analysis) had previously received a Bookstart pack. Generally, the families had received these one year prior to the Bookstart+ intervention. These packs are similar to the Bookstart+ pack in that they consist of a pack of age-‐appropriate books gifted by health visitors. However, they are gifted in the first year and the health visitor receives no formal training or instruction on how to gift the pack.
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As also described in the previous section, standard practice would always be to include some sign-‐posting to the library in all Bookstart packs including library leaflets and information. However, it is important to note that this was not done in relation to the packs distributed in the present trial where each pack did not include any information or leaflets on the local library.
2.4 Sample As stated above, the health visitors came from 4 geographical areas in Northern Health and Social Care Trust in Northern Ireland. Table 2 shows how many families were assigned to health visitors in each of the four areas. As can be seen, of the initial 462 families randomised, it was only possible for health visitors to collect questionnaires from 341 of these (73.8%). Moreover, and as also shown in Table 2, only 203 families returned a post-‐test questionnaire; making up 59.5% of those who had previously completed the pre-‐test questionnaire and just 43.9% of the original total number of families identified for the study. Table 2. Number of families and pre and post questionnaires completed for health visitors by region
Geographical location Number of families randomised
Families providing pre-‐test data (% of total)
Families providing pre-‐ and post-‐test data
(% of total) Antrim/Ballymena
116 96 (82.8%) 51 (44.0%)
Magherafelt/Cookstown
87 61 (70.1%) 37 (42.5%)
Coleraine/Ballymoney/Moyle
104 82 (78.8%) 55 (52.9%)
Larne/Carrickfergus/Newtownabbey
151 101 (66.9%) 59 (39.1%)
Missing Data
4 1 (25.0%) 1 (25.0%)
Total
462 341 (73.8%) 203 (43.9%)
The research process, and the nature of the attrition of families from the trial, is illustrated in Figure 1 overleaf.
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Figure 1: Selection of Families for the Randomised Controlled Trial Table 3 compares the characteristics of the control and intervention groups in relation to their mean scores on the three outcome variables at pre-‐test as well as their socio-‐economic status, levels of parental education and whether they had received a Bookstart pack before. As can be seen, the two groups were well matched with no statistically significant differences in relation to any of these six variables. This, in turn, provides confirmation that the initial randomisation process worked well in creating two matched groups. However, it can be seen from the previous Table 2 and Figure 1 above that there was substantial attrition during the various stages of testing so that there was only full data (i.e. pre-‐test and post-‐test data) for 43.7% of those families originally randomised. This could, potentially, introduce significant bias into the trial. To test for this, Table 4 compares the characteristics of the intervention and control groups against the same six variables but only for those families who remained in the trial until the end, and thus for whom full data were gathered. As can be seen, the two groups remained well matched with no statistically significant differences arising due to the levels of attrition. While there remains the possibility that there may be bias introduced to the trial due to these levels of attrition, Table 4 suggests that we can remain fairly confident in the internal validity of the trial.
Total Families assigned to health
visitors n=462
Health visitors returned a
questionnaire n=171
Family completed a post test
n=96 (40.9%)
Intervention n=235
Health visitors returned a
questionnaire n=170
Family completed a post test
n=107 (47.1%)
Control n=227
Health visitors did not return a questionnaire
n=64
Family did not complete a post test
n=75
Health visitors did not return a questionnaire
n=57
Family did not complete a post test
n=63
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Table 3. Means, standard deviations and significance of difference on variables at pre-‐test for all families for whom pre-‐test data were collected (n=341) Variable Summary Statistics Sig. Parent Attitudes Intervention m=3.85, sd=.73 Parent Attitudes Control m=3.86, sd=.66
p=.870, t=.164, df=334
Child Reading Intervention m=3.49, sd=.44 Child Reading Control m=3.51, sd=.44
p=.755, t=.312, df=339
Library Usage Intervention m=1.07, sd=1.05 Library Usage Control m=1.01, sd=1.06
p=.640, t=.468, df=333
Socio-‐economic Status Intervention m=5.52, sd=1.79 Socio-‐economic Status Control m=5.71, sd=1.76
p=.502, t=.673, df=174
Parent Education Intervention m=4.59, sd=1.17 Parent Education Control m=4.36, sd=1.33
p=.139, t=1.484, df=281
Bookstart Pack Before Intervention 71.0% Bookstart Pack Before Control 76.9%
p=.215, chi-‐square=1.536, df=1
Table 4. Means, standard deviations and significance of difference on variables at pre-‐test only for families for whom pre-‐test and post-‐test data were collected (n=203) Variable Summary Statistics Sig. Parent Attitudes Intervention m=3.94, sd=.73 Parent Attitudes Control m=3.85, sd=.68
p=.324, t=.988, df=200
Child Reading Intervention m=3.55, sd=.41 Child Reading Control m=3.57, sd=.41
p=.688, t=.403, df=201
Library Usage Intervention m=1.08, sd=1.02 Library Usage Control m=1.15, sd=1.12
p=.621, t=.495, df=197
Socio-‐economic Status Intervention m=5.66, sd=1.84 Socio-‐economic Status Control m=5.95, sd=1.80
p=.405, t=.836, df=110
Parent Education Intervention m=4.57, sd=1.19 Parent Education Control m=4.59, sd=1.28
p=.912, t=.111, df=175
Bookstart Pack Before Intervention 75.5% Bookstart Pack Before Control 78.5%
p=.617, chi-‐square=.251, df=1
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2.5 Measures As explained above, in the study there were three key outcomes investigated. Each of the outcomes is measured by a composite mean score from several items within the research questionnaire. A complete copy of the questionnaire used for the evaluation is provided in Appendix A1. Details of the three outcome variables are provided in Table 5, including the items (questions) that contribute to the score on each respective variable. The last column in this table is the Cronbach’s Alpha score for each measure. Cronbach’s Alpha scores represent the reliability of the scale. High reliability occurs when people consistently answer the questions within each outcome measure in a similar way. As can be seen, the Alpha scores for the major outcome variables suggest that all three measures are sufficiently reliable. In terms of validity, the measures would all appear to have good face validity and a factor analysis on each of the three measures in turn (not reported here) indicate that these measures also have good construct validity, with all three being uni-‐dimensional. Table 5. Major outcome variables and contributing items and Chronbach’s Alpha Variable Items1 Alpha
I like reading (Q.12) I find it hard to finish books (Q.12) It is important for me to be a good reader (Q.12) How often do you read books? (Q.13)
Parent Attitudes (parental attitudes to reading and books) How often do you buy books for yourself? (Q.13)
.80
How often do you or your partner read to your child? (Q.1) Do you have books for babies or toddlers in the home? (Q.2) What is your child’s attitude towards books? (Q.3)
Child Reading (parent and child attitudes to reading and sharing books)
What is your attitude towards reading with your baby/toddler? (Q.11)
.69
Are you or your child/children a member of your local library? (Q.4) Have you, for yourself or on behalf of a child, borrowed a book or other material from a local library in the last 3 months? (Q.5)
Library Use (family interaction with the library) Have you or your partner attended any baby or toddler-‐oriented
events at a local library? (Q. 6)
.67
2.6 Statistical Analysis 2.6.1 Summary of analyses The main analysis was conducted using multi-‐level regression modelling in order to account for the clustering of parents (level one) within health visitors (level two). Alongside the substantive analysis of the effects of the intervention as a whole on the three outcomes identified, further exploratory analyses were undertaken to assess whether Bookstart+ was having differential effects on parents depending upon: their socio-‐economic background; their levels of educational attainment; the
1 The number in parentheses refers to the question number of the item in the research instrument (see Appendix One)
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number of other children they have in the family; and the geographical area where they live. This further analysis involved developing the main multilevel models by including the appropriate interaction terms. Full details of all the models estimated in this analysis can be found in Appendix A2. 2.6.2 Calculation of Effect Sizes Effects were calculated using the multilevel models described above to estimate the post-‐test mean scores for the intervention and control groups once pre-‐test scores were controlled for. The specific effect size measure used here was the standardised mean difference calculated as the difference in these two mean scores divided by the pooled standard deviation for the post-‐test scores for both groups (i.e. Cohen’s d), and after controlling for any differences in pre-‐test scores. This method therefore generates effect sizes measures that allow for direct comparability with the effects of other programmes reported in Section 1.4 above (see Table 1).
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3. Findings
3.1 Parents’ self-‐perceptions about Bookstart+ Table 6 summarises parents’ responses to being asked how their family has used the Bookstart+ pack since receiving it. As can be seen, the books seem to have been used well. Two thirds of the intervention parents (66%) stated that they have used most of the Bookstart+ packs frequently and nearly all of the remaining parents (33%) stated that they had made some use of them. Only a negligible proportion (1%) said they had not used the packs at all. Table 6.Responses to question: “Since receiving it has your child used the pack?” Variable Frequency Percent Yes, we have used most or all of the books provided and we use them frequently (Q. 9)
51 66.2
Yes, we have made some use of the Bookstart books+ (Q.9)
25 32.5
No, we have not made use of the Bookstart books(Q.9)
1 1.3
Table 7 shows there were also positive responses regarding whether parents felt the books had made a difference in terms of their own behaviour. As can be seen, a small proportion of parents (7%) said they were unaware of the benefits of reading and that receiving the Bookstart+ pack had made them aware of these and thus encouraged them to read more with their children. Moreover, while a further 48% stated that they were already aware of the benefits of reading with their children, they stated that the Bookstart+ pack had encouraged them to read more than they would have done. Table 7.Responses to question: “In your own estimation, has receiving the Bookstart pack encouraged you or your partner to read more frequently to your child?” Variable Frequency Percent Yes, I was unaware of the benefits of reading with babies/toddlers and the packs have encouraged me to read more frequently with our child/children
5 6.7
Yes, I previously knew about the benefits of reading but have been encouraged by the Bookstart packs to read more frequently and/or become more engaged in reading with my children
36 48.0
No, I have always read to my children. Receiving the Bookstart packs made no difference.
34 45.3
No, reading doesn’t interest me and I don’t read to my children.
0 0%
Furthermore, it can be seen from Table 7 that he remaining parents (45%) chose the following response ‘No, I have always read to my children. Receiving the Bookstart packs made no difference’.
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However, this response is difficult to interpret as it includes two separate statements. Thus, of the 45% who selected this option it is not possible to determine: how many were simply responding to the first statement (‘No, I have always read to my child’); how many were responding specifically to the second statement (‘Receiving the Bookstart packs made no difference’); and/or how many were responding to both. Given the unreliability of this statement therefore, it is not possible to determine what precise proportion of parents felt that the Bookstart+ pack made no difference at all.
3.2 The effects of Bookstart+ on outcomes Table 8 summarises the findings of the trial in relation to the effects of the Bookstart+ intervention on the three outcome variables. As can be seen, the standardised effect sizes associated with the intervention in relation to each of the three outcomes are provided allow for direct comparisons of the effects of Bookstart+ with some of the other types of reading initiatives described in Section One. Table 8. Summary of Main Effects
Post-‐Test Mean Scores* (with Standard Deviations)
Outcome
Control Intervention
Effect Size [95% Confidence
Interval]
Significance
Parent attitudes to their own reading 3.72 (.77)
3.87 (.73)
+.192 [+.014, +.369]
p=.034
Parent attitudes to reading with their child
3.57 (.40)
3.60 (.36)
+.085 [-‐.069, +.240]
p=.279
Extent of library use 1.25 (1.18)
1.07 (1.06)
-‐.160 [-‐.342, +.003]
p=.055
*Adjusted to control for pre-‐test scores. In relation to the first outcome, there was evidence of a positive effect of Bookstart+ on parents' attitudes to their own reading, with the mean score of parents in the intervention group on the parent attitudes scale being higher (3.87) than that of parents in the control group (3.72), and once pre-‐test scores had been controlled for. This positive effect can be illustrated by reference to the parents’ responses to some of the individual questions asked. For example, while the vast majority of all parents (95%) agreed with the statement that “it is important for me to be a good reader”, it can be seen from Figure 2 that those parents who received the Bookstart+ pack tended to feel more strongly about this than those in the control group. Interestingly, no such differences in response to this question were evident at pre-‐test. In relation to the second outcome, of parents’ attitudes to their child reading, it can be seen that there is some potentially encouraging signs of a slight improvement with the mean score of parents in the intervention group on the child reading attitudes scale (3.60) being marginally higher than that of parents in the control group (3.57). However, given the small size of this effect (d = +.085), this difference was not statistically significant and therefore cannot be reported as a reliable finding.
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For the third outcome, it can be seen from Table 8 that there is evidence of a negative effect (d = -‐.160), with parents in the intervention group showing a reduction in their mean score on the library use scale (1.07) in comparison with those in the control group (1.25). Again, this effect can be illustrated in the parents’ answers to some of the individual questions they were asked. Thus, in response to the question:“Have you, for yourself or on behalf of a child, borrowed a book or other material from a local library in the last 3 months?” it can be seen from Figure 3 than while nearly half (47%) of those in the control group answered “yes” at post-‐test whereas only a third (33%) of those in the intervention group did the same.
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Besides this main analysis, further exploratory analyses were undertaken to examine whether the effects of Bookstart+ may have varied in relation to parents from differing socio-‐economic backgrounds, parents with differing levels of educational attainment, parents with differing numbers of other children in the home and parents from differing geographical areas. In relation to all three outcomes, however, no evidence was found of such differential effects. In other words, the effects of Bookstart+ tended to be similar regardless of these background characteristics. Full details of these additional analyses are provided in Appendix A2.
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4. Summary and Conclusions
4.1 Summary and discussion The findings presented in this report are very encouraging in many respects. It is clear that the Bookstart+ packs are viewed very favourably by the parents that received them. Nearly all of the parents appeared to make good use of the packs and just over half of the parents felt that receiving the pack had definitely encouraged them to do more reading with their children. Moreover, these perceptions are supported by the findings from the randomised controlled trial that has provided strong and robust evidence that the intervention is leading to positive change in the parents’ attitudes towards reading. Indeed the size of the effect found in relation to this (d=+.192) is in the range of what would be expected for a low-‐intensity, low-‐cost intervention as this one. There is also some potentially encouraging signs of a smaller positive change in parents’ attitudes to their child reading (d=+.085), although this change is not statistically significant and therefore cannot be reported as a reliable finding in its own right. This finding would suggest that it would be beneficial for Bookstart+ to consider ways of increasing the emphasis placed on encouraging parents to read with their children. This could be done, for example, through placing a greater emphasis on the benefits of reading with young children and of some of the simple, practical ways this can be done on a regular basis by parents in the health visitor demonstrations. In addition it would be worthwhile considering sending out short, reminder letters to parents as a follow-‐up to the gifting of the packs. These letters could include a brief, attractive leaflet that seeks to reinforce for parents the main information and guidance provided in the demonstration of the Bookstart+ packs, especially around the importance of reading with children. The one negative effect in relation to the reduction in use of the local library by parents who received the Bookstart+ pack is a matter of concern. The reasons for this need to be explored further. However, one plausible explanation is that being given books directly in the home could reduce the need for parents, in the short-‐term, to visit a local library. As such, while there may be an initially negative effect this could conceivably turn into a positive effect in the medium to longer-‐term as the initial receipt and use of such books increase the parents’ motivation to seek out more from their local libraries and elsewhere. Unfortunately, it is not possible to assess whether this is the case or not from the evidence generated from this present trial as it has not included a longitudinal element. However, regardless of whether such a negative effect is short-‐term or not, it is something that Booktrust needs to address. In this regard it is worth noting that in the Bookstart+ packs sent out for the present trial, none actually contained inserts providing details and information on local libraries for the parents. While it is not possible to assess the extent to which this was a contributory factor, it does suggest the need to ensure that such promotional information is included in all packs before they are distributed. Beyond this, it would also be beneficial for Booktrust to consider how they might promote the early use of local libraries by families further, either through the demonstration that health visitors provide and/or the information provided in the packs and possibly subsequently.
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It may also be worthwhile local libraries considering increasing the events they organise that are targeted at parents with young children and ensuring that these are clearly advertised in the Bookstart+ packs and/or any follow-‐up letter than is sent out.
4.2 Recommendations The findings, as outlined and discussed above, give rise to a number of specific recommendations:
1. Given the evidence presented in this report of the proven effectiveness of Bookstart+ on parental attitudes towards reading, Booktrust should be encouraged strongly to develop and expand the programme further.
2. In developing the intervention further, it would be beneficial for Booktrust to consider how a
greater emphasis could be placed on encouraging parents to read more with their children.
3. It is important that Booktrust explore further the reasons for the negative effect on library use among families that received the Bookstart+ pack and put into place strategies to mitigate this effect prior to rolling out the programme on a larger scale.
4. A further randomised controlled trial evaluation of the Bookstart+ intervention should be
undertaken, using a larger sample and possibly run on a UK-‐wide basis. Such a trial would allow for the development of more detailed and sensitive outcome measures and also a more comprehensive analysis of the potential mediating influences of a number of key contextual factors. The trial would also allow the effectiveness of the intervention to be tested should any further refinements to the programme be made in line with the recommendations above and, in relation to library use, could test the longer-‐term effects of the Pack if an appropriate longitudinal component is added.
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References Bookstart (2010) Bookstart+: For toddlers aged 18-‐30 months. Viewed 18th November 2010 http://www.bookstart.org.uk/Resources/Bookstart-‐packs/Bookstart+ Hepburn, E., Egan, B., Flynn, N. (2010) Vocabulary acquisition in young children: The role of the story. The Journal of Early Childhood Literacy. 10, 2: 159-‐182 Kovalik, (2010) Evaluation des Projekts -‐ Buchstart Schweiz. Bibliomedia Schweiz Viewed 26th October2010 http://www.leseforum.ch/fr/myUploadData/files/2010_3_Kovalik.pdf Marks, G. N., Cressell, J., & Ainley, A. (2006). Explaining socioeconomic inequalities in student achievement: the role of home and school factors. Educational Research and Evaluation, 12(2), 105– 128. Moore, M. & Wade, B. (2003). Bookstart: a qualitative evaluation. Educational Review, 55(1): 3. Phillips, L. M., Norris, S. P., Mason, J. M., & Kerr, B. M. (1990). Effects of early literacy intervention on kindergarten achievement. National Reading Conference Yearbook, 39, 199–207. Schickedanz, J. A., & McGee, L. M. (2010). The NELP report on shared story reading interventions (chapter 4): Extending the story. Educational Researcher, 39, 323–329. Slavin, R.E., Lake, C., Chambers, B., Cheung, A., & Davis, S. (2009) Effective beginning reading programs: A best evidence synthesis. Baltimore, MD: Johns Hopkins University, Center for Data-‐Driven Reform in Education. Viewed 26th October http://www.bestevidence.org/reading/begin_read/begin_read.htm Smyth, E., Whelan, C.T., McCoy, S., Quail, A. & Doyle E. (2010) Understanding Parental Influence on Educational Outcomes Among 9 Year Olds in Ireland: The Mediating Role of Resources, Attitudes and Children’s Own Perspectives. Child Indicators Research. Volume 3, Number 1, 85-‐104, Vanobbergena, B., Daemsa, M., Van Tilburg, S. (2009) Bookbabies, their parents and the library: an evaluation of a Flemish reading programme in families with young children. Educational Review, 61, 3; 277 -‐ 287 Wade, B. and Moore, M. (1993) Bookstart. London: Book Trust. Wade, B. and Moore, M. (1996) Children’s early book behaviour. Educational Review 48: 283-‐288. Wade, B. and Moore, M. (1998) An Early Start with Books: Literacy and Mathematical Evidence from a Longitudinal Study. Educational Review 50 (2), pp.135-‐45. Wade, B. and Moore, M. (2000) A sure start with books. Early Years 20(2):39-‐46.
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Appendices
A1. Research Instrument ................................................................................................. 33 A2. Statistical Models....................................................................................................... 41
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Appendix A1: Research Instrument
Bookstart+
Randomised Trial
Evaluation 2009
Some Questions About Your Child What is your child’s first Name ______________ Surname ____________________
Are they........ Male Female
What age is you child? _____________ months
Does your child have special educational needs? Yes No If yes, what is the special educational need/s?__________________________________ _______________________________________________________________________.
1. How often do you or your partner read to your child?
A On two or more occasions every day
B Once a day
C A few times a week
D Maybe once or twice a week
E Maybe once a week or less
F Never
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2. Do you have books for babies or toddlers in the home? A Over 40 books
B Between 20-‐ 40 books
C Between 10-‐19 books
D Less than 10 books
E None
3. What is your child’s attitude towards books? A Uninterested: doesn’t know what to do
with them
B Little interest: no strong inclination to look at books
C Quite interested; enjoys looking at books when encouraged
D Very interested; enjoys books with and without encouragement, handles pages, points to pictures, etc.
4. Are you or your child/children a member of your local library? YES NO
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5. Have you, for yourself or on behalf of a child, borrowed a book or other material from a local library in the last 3 months? YES
NO
6. Have you or your partner attended any baby or toddler-‐oriented events at a local library? YES
NO
7. Has your family received a Bookstart pack before? YES
NO Go to Q.11
8. When and how did you receive the bookstart pack? When (date)_________________________ How (e.g. from a health visitor, Through Sure start)___________________________ ______________________________________________________________________ 9. Since receiving it has your child used the pack? (Tick one answer only) A Yes, we have used most or all the books
provided and we use them frequently
B Yes, we have made some use of the Bookstart books
C No, we have not made use of the Bookstart books
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10. In your own estimation, has receiving the Bookstart pack encouraged you or your partner to read more frequently to your child? N/A
A Yes, I was unaware of the benefits of reading
with babies/toddlers and the packs have encouraged me to read more frequently with our child/children
YES
B Yes, I previously knew about the benefits of reading but have been encouraged by the Bookstart packs to read more frequently and/or become more engaged in reading with my children
NO
C
No, I have always read to my children. Receiving the Bookstart packs made no difference.
D
No, reading doesn’t interest me and I don’t read to my children.
Evaluation of Bookstart+| 37
Some Questions About You
11. What is your attitude towards reading with your baby/toddler? A Uninterested: not my kind of thing
B Very little interest: not really a priority
C Quite interested: a good thing to do
D Very interested: strongly committed to encouraging my child to read
12. Please circle the items that apply to you I like reading……….………………………... Strongly
Agree Agree Don’t
know Disagree Strongly
Disagree
I find it hard to finish books……………….…. Strongly Agree
Agree Don’t know
Disagree Strongly Disagree
It is important for me to be a good reader……… Strongly Agree
Agree Don’t know
Disagree Strongly Disagree
It is important for my child to be a good reader...
Strongly Agree
Agree Don’t know
Disagree Strongly Disagree
13. Please circle the items that apply to you How often do you read books? ………..…. Daily Once or
twice a week
Once or twice a month
Very Rarely
Not at all
How often do you buy books for yourself?...… Daily Once or twice a week
Once or twice a month
Very Rarely
Not at all
How often do you buy books for your child?....
Daily Once or twice a week
Once or twice a month
Very Rarely
Not at all
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Some Questions About You and Your Household
(Please remember you do not have to answer any of these questions if you do not want to but they will help in our evaluation of the Bookstart programme and all answers will be treated in the strictest confidence.) 14. What is your relationship to the child? Mother …………….. Father ……………… Stepfather …………. Stepmother ………… Grandfather ……….. Grandmother ............. Legal Guardian...…… If yes, are you male or female? …... Male female Other……………….. If OTHER, please state relationship _______________________. 15. Do any other children live in your house? ………………………… Yes No If Yes, how many? ______________. What are the ages of the children? _________________. 16. What other adults live in your house? (Please tick boxes that apply) No other adults ……………………………. Father ……………………………………… Stepfather (including mother’s partner) ...…. Mother ……………………………………... Stepmother (including father’s partner)……. Grandparents…..…………………………… If YES, How many?___________
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Other………………… If OTHER, please state relationship to the child ______________. 17. In which country were you born? ____________________ 18. What language is most frequently spoken in your home? _________________________. 19. Within your household, what is the highest level of parental education (full time or part time) which has been completed to date? (Please tick only one box for each parent, where applicable)
Mother / Father / Step Mother Step
Father
Primary or below………………………..................... ............…………… Lower Secondary …………………………………………. ………………………
Upper Secondary ………………………….…………….. ……………………… Post-‐Secondary Non-‐Tertiary………………………. ……………………..
Non-‐Degree (Certificate/Diploma) …………….. ……………………. Degree or Higher ………………………………………… ……………………
Other………………………………………………………….. …… Please State _______
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20. Please tick the main employment status of each parent or guardian that live in your household. (Please tick only one box for each parent, where applicable)
Mother / Father / Step Mother Step
Father At Work……………………………………………………….. …………………………… Seeking regular work for the first time ……… …………………………… Unemployed……………….……………………………… …………………………… Student …………………………………………………….. ……………………………. Looking after home / family …………..………… …….........……………… Retired from employment ……..………………… ……………………………. Unable to work due to permanent disability/sickness ……………………………………… …………………………….. Other…………………………………………………………. ……………Please state _________ 21. Please tell us the name of the job of each parent that lives in your household. If not currently working, please indicate the most recent job. Mother (Step Mother) most recent employment?_________________________. Father (Step Father) most recent employment?___________________________. 22. Last month, what was the total (take home) income of your household from all sources? Including employment and benefits? £______
Evaluation of Bookstart+| 41
Appendix A2: Statistical Models Table 8. Statistical Models for Parent Attitudes outcome
Statistical Models (Standard Errors in Parentheses)
Sub-‐group analyses testing whether the following variables had an impact on the effectiveness of the intervention:
Independent
Variables in the
Model
Main Model
SES Parent Education
Siblings Bookstart Pack Before
Area
Intervention1 .145(.069) .227(.287) .424(.285) .231(.119) .190(.142) .242(.136) Pre-‐test score .815(.049) .910(.065) .830(.055) .825(.048) .797(.050) .809(.049) SES2 .010(.032) SES_Int3 -‐.015(.047) Parent Education4 .018(.039) Parent Educat_Int -‐.067(.060) Siblings5 -‐.016(.105) Siblings_Int -‐.148(.145) Bookstart Pack6 .077(.114) Bookstart_Int -‐.031(.162) Area7_mag .148(.148) Area_col -‐.060(.125) Area_lar .070(.123) Int_amag -‐.311(.211) Int_acol -‐.085(.188) Int_alar -‐.057(.185) Constant .579(.194) .130(.277) .468(.257) .563(204) .591(.207) .576(.209) Ωu .000(.000) .018(.032) .000(.000) .000(.000) .000(.000) .000(.000) Ωe .235(.023) .177(.038) .225(.024) .226(.023) .230(.023) .230(.023) -‐2*Log Likelihood 279.506 133.068 235.619 269.088 272.032 274.600
1 Type of group (coded Intervention=1, Control=0) 2 Socio-‐economic status 3 Terms ending with the suffix “_Int” indicate the interaction term between that variable and the variable “Intervention” 4 Parental education level 5 How many siblings there were in the house 6 Whether or not the family had received a Bookstart pack before 7 Area variables were in four geographical categories: Antrim/Ballymena (acted as the reference category); Magherafelt/Cookstown, (dummy variable = mag); Coleraine/Ballymoney/Moyle, (dummy variable = col); Larne/Carrickfergus/Newtownabbey, (dummy variable = lar)
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Table 9. Statistical Models for Child Reading outcome
Statistical Models (Standard Errors in Parentheses)
Sub-‐group analyses testing whether the following variables had an impact on the effectiveness of the intervention:
Independent
Variables in the
Model
Main Model
SES Parent Education
Siblings Bookstart Pack Before
Area
Intervention1 .032(.030) .121(.145) .120(.124) .114(.052) .034(.063) .091(.059) Pre-‐test score .760(.036) .654(.060) .730(.041) .750(.036) .760(.036) .770(.036) SES .005(.016) SES_Int -‐.014(.024) Parent Education .017(.018) Parent Educat_Int -‐.019(.026) Siblings .060(.046) Siblings_Int -‐.111(.064) Bookstart Pack .038(.050) Bookstart_Int -‐.002(.071) Area_amag .013(.064) Area_col .005(.054) Area_lar -‐.083(.053) Int_amag -‐.126(.091) Int_acol -‐.110(.082) Int_alar -‐.006(.080) Constant .912(.131) 1.27(.024) .945(.145) .901(.134) .882(.139) .895(.134) Ωu .000(.000) .003(.016) .000(.000) .000(.000) .000(.000) .000(.000) Ωe .045(.004) .049(.017) .045(.005) .043(.004) .045(.004) .043(.004) -‐2*Log Likelihood -‐53.898 -‐14.108 -‐47.716 -‐60.006 -‐52.754 -‐61.690
1 See Table 8 footnotes for a description of all variables
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Table 10. Statistical Models for Library Interactions outcome
Statistical Models (Standard Errors in Parentheses)
Sub-‐group analyses testing whether the following variables had an impact on the effectiveness of the intervention:
Independent Variables in the Model Main
Model
SES Parent Education
Siblings Bookstart Pack Before
Area
Intervention1 -‐.181(.094) .200(.453) .177(.399) -‐.282(.168) -‐.382(.199) -‐.070(.186) Pre-‐test score .846(.044) .847(.062) .837(.049) .843(.044) .856(.045) .846(.044) SES .019(.050) SES_Int -‐.057(.075) Parent Education .090(.055) Parent Educat_Int -‐.078(.084) Siblings -‐.123(.148) Siblings_Int .139(.206) Bookstart Pack -‐.240(.161) Bookstart_Int .260(.226) Area_mag .241(.207) Area_col .263(.170) Area_lar .310(.167) Int_amag -‐.047(.289) Int_acol -‐.174(.258) Int_alar -‐.237(.255) Constant .368(.082) .214(.315) -‐.024(.258) .463(.140) .546(.143) .169(.129) Ωu .000(.000) .000(.000) .000(.000) .000(.000) .000(.000) .000(.000) Ωe .438(.044) .500(.068) .451(.049) .439(.044) .435(.044) .427(.043) -‐2*Log Likelihood 398.422 233.668 351.402 396.704 395.086 393.524
1 See Table 8 footnotes for a description of all variables
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Evaluation of Bookstart+| 45
Centre for Effective Education School of Education Queen’s University Belfast 69-‐71 University Street Belfast BT7 1HL Northern Ireland Ph: +44 (0)28 9097 5051 Fax: +44 (0)28 9097 5066 Email: cee@qub.ac.uk Web: www.qub.ac.uk/cee