Keele Research Repository

There is a need for research that provides an evidence base for the pharmacotherapy of people with mental disorders. The abundance of digital data in recent years has facilitated pharmacoepidemiology in the form of observational comparative effectiveness studies at the population level. Advantages are large patient samples, coverage of under-researched sub-populations and naturalistic conditions. Pharmacoepidemiology is also cheaper and quicker to carry out than RCTs, meaning that issues regarding generic medication, stopping medication (deprescribing) and long-term outcomes are more likely to be addressed. Methods can also be extended to pharmacovigilance and drug repurposing. Drawbacks of observational studies come from the non-randomised nature of treatment selection, and the inherent risk of confounding by indication. Potential methods for managing this may include active comparison groups, inter-individual designs, propensity scoring and instrumental variables. Many of the more rigorous pharmacoepidemiology studies have been strengthened through multiple triangulated analytic approaches to improve confidence in inferred causal relationships. With these developments in data resources and analytic techniques, it is encouraging that guidelines are beginning to include evidence from robust pharmacoepidemiogical studies alongside RCTs. Collaboration between guideline-writers and researchers involved in pharmacoepidemiology may help researchers ask the questions that are important to policy-makers and ensure that results get integrated into the evidence-base. Further development of statistical and data science techniques, alongside capacity building in terms of data resources, a wider researcher base and public engagement, will be necessary to take full advantage of future opportunities.