Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases.OBJECTIVE
 UK general practices contributing to QResearch or Clinical Practice Research Datalink (CPRD), linked to hospital, mortality, social deprivation, and cancer registry (QResearch only) data.


 Separate results from QResearch or CPRD were combined.



QResearch
Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases.OBJECTIVE

CPRD databases