Data management

in the field

Ari Haukijärvi

2nd EHES training seminar

Division of tasks and preparation of the fieldwork

• The Central Office - Overall data management preparation and coordination during the fieldwork

• Arranging computer equipment and networks for the fieldwork teams (if computerized data collection is used):

• Planning the structure of computer network(s) and equipment• Establishing and customizing the network(s)• Installing the survey software• Planning of software updates during the fieldwork• Testing

• Training, responsibilities, and support of the fieldwork teams:

• In putting up the network (if needed)• In using the data recording equipment and software• Issuing responsibilities to team members• Providing instruction manuals for the fieldwork• Arranging helpdesk during the fieldwork

Division of tasks and preparation of the fieldwork

• The Central Office

• Coordinating the fieldwork data management• Database(s) maintained in the Central office can be used to

monitor and control the fieldwork:• Scheduling appointments• Creating invitations, lists of appointment schedules, calendars,

etc.• Storing fieldwork inventory data• Generating feedback

• Receiving and processing the survey data

Division of tasks and preparation of the fieldwork

• The Fieldwork teams

• Setting up the equipment and network connections (if needed) at the fieldwork site

• Basic technical knowledge in using equipment and software for data collection

• Responsibilities in backing up and transferring the data• Named person(s) or all team members?

Collecting the survey data

• Data from• Questionnaires and interviews• Physical measurements• Laboratory tests and samples

• … are recorded• on paper forms• on workstations, from which data files are copied to a

local (fieldwork team) network’s server• directly to the local (fieldwork team) network's server• directly to the central survey database (in the Central

Office)

Example 1 (System architecture of Health 2000 Survey)

Example 2 (MAAMU)

Data error checking

• Routine checking procedures:• Visual checking of key items at examination site• In computer-assisted data collection automatic built-in

software checks at examination site• Extensive checking for all computerized data (in the

Central Office)

• … to ensure:• complete data records• no errors• no lost or mixed-up records

Data management in the field- Key issues

• Identification

• Data confidentiality and security

• Backing up the data

Identification

• Follow-up of participants through the survey process

• to make sure that correct data corresponds to each subject, and

• to monitor in which phase of the survey each subject is

• by means of• unique subject ID code (Serial number): used to identify

the subject throughout the survey• barcodes (referencing to the subject ID)

• in survey forms• in laboratory samples

Data confidentiality and security

• Paper forms• Not to be left alone for unauthorized to see or get lost• Clear responsibilities in collecting and storing• Sealed containers (also during shipments)• No personal information included > subject ID code

• Data in electronic format• Locking workstations and server computers when not used• Safe place for equipment when not used• Encrypted hard disks• Encrypted data transfers• Data should not be archived in personal directories or local

computers' hard drives• The personal data of survey subjects should be encrypted and

available only to persons who have authorized access

Backing up the data

• The data need to be backed up• regularly• on external storage device (e.g. external hard drive,

optical disk, another computer, etc.) separate from the original data source

• ’Remote’ backup: Data transfer to the Central Office

• Logging the data transfers

Data correction/documentation

• Changes to the data • According to the rules for data verification and

correction, specified in the national manual• By trained persons• Need to be documented:

• Version of data• What was changed• Reason for the change• Time of the change

• The original raw data is backed up and unchanged