Table 4 Insights/key messages from the OPTI-SCRIPT process evaluation

• Complex interventions in primary care are often not implemented and utilised as intended.

• Intervention delivery may vary by practice characteristics such as number of GPs and practice resources.

• Recruitment continues to be one of the most challenging aspects of conducting trials in primary care. In this setting, computerisation of patient identification would decrease the requirements placed on GPs at the start of the study and speed up the recruitment process.

• Involving patients in medication reviews has the potential to decrease inappropriate prescribing.

• Targeting a smaller number of specific medication groups or “cardinal PIPs” emerged as an important facilitator in overcoming workload barriers.

• Process evaluations are more informative when they incorporate both qualitative and quantitative research methods.