Information on individuals eligible to participate in ALSPAC is currently available through linkage to the ONS (deaths and cancer registrations, 99% coverage of the ‘eligible sample’), the National Pupil Database (∼82% coverage of the ‘eligible sample’ depending on time point) and the General Practice Research Database11 (∼4% coverage of the ‘eligible sample’). The Project to Enhance ALSPAC through Record Linkage (PEARL) is extending the use of linkage to administrative data to enhance the ALSPAC data resource and address issues of possible participation bias. Existing or intended administrative data sources used by ALSPAC are listed in Table 8. Table 8ALSPAC linkage to health and administrative records Health records aPrimary care electronic patient recordsbThe General Practice Research Database (GPRD)aHospital Episodes Statistics (HES), bCancer and Deaths Registry, NHS Information Centre and Office for National StatisticsbAd hoc data extraction from hospitals, bgeneral practice, bopticians and records of other health care providers (e.g. records of childhood seizures)Education records bSchool records; NPD schools data, Department for EducationbFurther education and work-based learning; Individual Learner Record (ILR) database, Department for Business, Innovations and SkillsbHigher education; Higher Education Statistics
