2011 CYP Update: Newly Calculated Factors Process, Calculation, Justification, Implications.
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Transcript of 2011 CYP Update: Newly Calculated Factors Process, Calculation, Justification, Implications.
2011 CYP Update: Newly Calculated FactorsProcess, Calculation, Justification, Implications
Outline
Process/Methodology used for the update
Items included in factor calculations
Look at methods through 3 categories– Those with recommended changes
– New methods
– Those with no recommended changes from the 2000 CYP factors
Process/Methodology Used for the Update
Peer reviewed literature review
Gray literature review– Online search engine (Rollyo)
– Organizational and individual contacts
Secondary analysis of DHS data
Utilization of data from articles and analysis to determine justification of method updates
Selection of specific data/articles to be included in new estimates– Real world usage
– Length of follow-up in studies
– Impact of inclusion/exclusion of articles on estimates (continuation rates)
Method specific calculations
Consultative meetings throughout
Factors Included in CYP Calculations
Use Effectiveness - all methods
Duration of use - long acting and permanent methods and Fertility
Awareness Methods (continuation rates and age)
Coital Frequency - condoms, spermicides (coitus-dependent
methods)
Consistency of Use - condoms, spermicides (coitus-dependent
methods)
Wastage - pills, condoms, spermicides
Overlapping Coverage*- all methods in 2000
* Use of a method during postpartum amenorrhea
Overlapping Coverage (Postpartum Amenorrhea)
2000 estimates used secondary analysis of DHS data to estimate number of postpartum amenorrheic women using any method.
Method Number of Countries
Percentage Amenorrheic*
2000 CYP with
Overlapping Coverage
2000 CYP without
Overlapping Coverage
Pill 18 1.7% 14 14
IUD 14 2.6% 3.7 3.8
Injection 12 5.4% 4.2 4
Condom 19 5.9% 105 98
* Percentage of women less than 6 months postpartum that are currently amenorrheic and using any method.
Overlapping Coverage
Method Number of Countries
2011
Percentage Amenorrheic
2011
Percentage Amenorrheic
2000
Pill 1 2.6% 1.7%
IUD 1 1.2% 2.6%
Injection 2 2.6% 5.4%
Condom 2 3.4% 5.9%
Updated analysis using DHS after 2004.
Updated analysis using DHS after 2004.
Going to disregard overlapping coverage during postpartum amenorrhea
Methods with CYP Factor Changes
IUD
Implants
Sterilization
Natural Family Planning (Fertility Awareness Methods)
IUD
2000 USAID CYP Factor (with rounding): 3.5 CYP per IUD inserted
Equation:
Average duration * effectiveness * proportion not overlapping
3.9 years * 96.4% * 97.4% = 3.6
Justifications for recommending a change:– Change in average duration of use (continuation/discontinuation)
– Eliminating effectiveness from the equation because it is included in average duration of use
IUD Average Duration of Use
Calculated by fitting an exponential decay curve to the continuation data (R=ae-
rt)
From 4 articles:
Ali et al. 2011 (secondary analysis of DHS data)
2 WHO studies providing 12 years of follow up (clinical trials)
Jenabi et al. 2006 providing 1 month continuation rates
Uses Ali data for the first 3 years and then applies the curve from the WHO data to the Ali data for years 4-10.
Truncated at 5 and10 years
Average duration of use is 4.6 years
Compared to 3.9 years in 2000
Changes CYP from 3.5 to 4.6
CYP for 5 year IUD is 3.3 0
0.2
0.4
0.6
0.8
1
1 2 3 4 5 6 7 8 9 10 11
Implants
2000 USAID CYP Factor: 3.5 CYP per implant (Norplant)
2.0 CYP per implant (Implanon, added later)
3.5 CYP per implant (Jadelle, added later)
Equation:
Average duration * effectiveness
3.6 years * 100% = 3.6
Justifications for recommending a change:– Change in average duration of use (continuation/discontinuation)
– Addition of Sino-Implant (II)
– Eliminating effectiveness from the equation because it is included in average duration of use
Implant Duration of Use
Calculated by fitting an exponential decay curve to the continuation data (R=ae-
rt)
Uses Norplant data to estimate the curve
Based on 4 studies: 3 doing secondary analysis of DHS data and one study of real world use in Senegal*
Factors are for 3, 4, and 5 year implants.
Due to differences in country registration duration
* Tuladhar et al. 1998, Fathonah et al. 2000, African Population and Health Research Center 2001, Ba et al. 1999
Implant Duration of Use
3 Year Implant: 2.4 years use
2.4 CYP per insertion
4 Year Implant: 3.0 years use
3.0 CYP per insertion
5 Year Implant: 3.6 years use
3.6 CYP per insertion
0
0.2
0.4
0.6
0.8
1
0 1 2 3
3 Year Implant
0
0.2
0.4
0.6
0.8
1
0 1 2 3 4 5
5 Year Implant
0
0.2
0.4
0.6
0.8
1
0 1 2 3 4
4 Year Implant
Sterilization
2000 USAID CYP Factor:– Asia 10 CYP
– Latin America 10 CYP
– Africa 8 CYP
– Near East/North Africa 8 CYP
Equation:
Mean age at time of sterilization, discounted for reduced fertility due to age, adjusted for higher parity among women opting for sterilization
Justifications for recommending a change:– Change in mean age at time of sterilization
Sterilization
Region Number of Countries
2011
CYP Factor2011
CYP Factor2000
Africa 25 9.3 8
Asia 7 10.3 10
LAC 5 10.5 9
2011 CYP Global Factor: 10
Sterilization
Discussion Points:– Different methodological approaches
> Fertility and parity adjustments (USAID)
> Mortality adjustments (Marie Stopes)
> Weighted averages used for regional estimates (Marie Stopes)
Natural Family Planning
2000 USAID CYP Factor: 2 CYP per trained adopter
Terminology change: Fertility Awareness Based Methods (FAM)
Standard Days Method (SDM)
Based on average duration of use- 1.5 years
2011 CYP Factor: 1.5 CYP per trained adopter
New Methods
Vaginal Ring
Contraceptive Patch
CYP of 15 for each, based on CYP for oral contraceptives
Methods Without CYP Factor Changes
Oral Contraceptives
Condoms– Male
– Female
Spermicides
Injectables– Depo
– Noristerat
– Cyclofem
Emergency Contraception
Oral Contraceptives
2000 USAID CYP Factor (with wastage adjustment): 15 cycles per CYP
Equation:
Number required / effectiveness / proportion not overlapping
13 / 92.4% / 98.3% = 14
Justification for No Recommended Change:• New effectiveness data does not support a change• No change in result with the elimination of overlapping coverage• No new data on wastage
Condoms and Spermicides
2000 USAID CYP Factor (with wastage adjustment): 120 units per CYP
Equation:
Number required (coital frequency, consistency of use) / proportion not overlapping
98 / 94.1% = 105
Condoms and Spermicides
Based on Rutenberg’s 1993 analysis: The Fertility Impact of Inconsistent Condom Use of Contraception.
Coital frequency of 5.6 based on secondary analysis of DHS data.
Assumes condoms are used for 50% of coital acts among those reporting themselves to be condom users.
Consistency of Use
Average Monthly Coital Frequency
Always (100%)
Most of the time (75%)
Sometimes (50%)
Infrequently (25%)
Low (1-4) 29 32 35 39
Low to Moderate (5-6) 65 80 98 120
Moderate to High (7-8) 100 141 198 275
High (9-10) 136 217 344 537
Condoms and Spermicides
Justification for No Recommended Change:– Coital frequency data is no longer collected in DHS so there is a lack of
comparable data.
– Minimal change from elimination of overlapping coverage.
– No new data on wastage.
Injectables
2000 USAID CYP Factor: 4 doses per CYP (Depo Provera)
6 doses per CYP (Noristerat)
13 doses per CYP (Cyclofem)
Equation (Depo Provera):
Average duration (biologically) / effectiveness / proportion not overlapping
4 / 100% / 94.6% = 4
Justification for No Recommended Change:– New effectiveness data does not support a change.
– No change from elimination of overlapping coverage.
Emergency Contraception
2000 USAID CYP Factor (added later): 20 doses per CYP
Equation:
CYP for Pills / effectiveness
15 / 75% = 20
Justification for No Recommended Change:– Methodology developed after 2000 with input from various experts, no
need to modify
– New effectiveness data does not support a change.
Methods Not Changing
Method 2000 CYP Conversion Factor
Oral Contraceptives 15 cycles per CYP
Condoms 120 units per CYP
Female Condoms 120 units per CYP
Vaginal Foaming Tablets 120 units per CYP
Depo Provera Injectable 4 doses per CYP
Noristerat Injectable 6 doses per CYP
Cyclofem Monthly Injectable 13 doses per CYP
Methods with Changing Factors
Copper T 380-A IUD 3.5 CYP per IUD inserted
Norplant Implant 3.5 CYP per implant
Implanon Implant 2.0 CYP per implant
Jadelle Implant 3.5 CYP per implant
Emergency Contraceptive Pills 20 doses per CYP
Natural Family Planning (SDM) 2 CYP per trained, confirmed adopter
LAM 4 active users per CYP (or 0.25 CYP per user)
Sterilization Asia Latin America Africa Near East/North Africa
10 CYP10 CYP8 CYP8 CYP
Issues for Discussion
Sterilization methodology
Free vs. sold condoms
Continuation differences by provider
Limitations of using DHS data
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