Table 1.

Characteristics of trials and interviewees

Trial	Clinical topic	Primary or secondary care	Trial outcome	Follow-up period	How trial outcome collected	Interviewees
1	Obesity	Primary	Change in Body Mass Index (BMI) z-scores	12 months	Home visit	Chief investigator 2 x research fellow trial administrator n = 4
2	Renal	Secondary	Physical function	12 months	Clinic visit	Chief investigator 3 x research nurse senior trial manager trial manager n = 6
3	Depression and cancer	Primary and secondary	Clinical depression score	24 weeks	Home/clinic visit or telephone contact	2 x research associates research nurse trial manager n = 4a
4	Fall prevention	Primary and secondary	Rate of falls	12 months	Postal by monthly falls calendars	Chief investigator research associate trial manager n = 3
5	Dementia	Primary	Goal setting interview	9 months	Home visit	Chief investigator trial manager n = 2

^aCI did not respond to invitation