A review of current practice in the design and assessment of internal pilots in UK NIHR clinical trials

Table 2 Details of the assessment of the internal pilots

	Frequency (%)
Design followed? (Yes/No)^a
Yes	49 (91%)
No	5 (9%)
Extended due to poor recruitment	2 (40%)
Internal pilot delayed	3 (60%)
Committees involved in review^b
IDSMC only	3 (6%)
TSC only	17 (35%)
IDSMC, TSC	23 (47%)
IDSMC, TSC, TMG	2 (4%)
TSC, sponsor	3 (6%)
Continuation to main trial? (Yes/No)
Yes, met criteria	33 (58%)
Yes, did not meet criteria	14 (25%)
Underwent a second review^c	5 (36%)
Continued with close monitoring	3 (21%)
Recovery plan put in place	3 (21%)
No reported actions taken	4 (29%)
Yes, unclear whether criteria met	9 (16%)
Decision on hold	1 (2%)
No	0 (0%)
Number of planned pilot sites given?^d (Yes/No)
Yes	44 (79%)
No	12 (21%)
If yes, specifically named?
Yes	16 (36%)
No	28 (64%)
Number of planned pilot sites
Median	6 (5, 10)
(interquartile range (IQR))
Min, Max	2, 80
Number of planned sites for full trial^f
Median (IQR)	20 (13, 30)
Min Max	3, 300
Adherence to plan regarding number of pilot sites?^e (Yes/No)
Yes	28 (72%)
No	10 (26%)
Opened further sites	6 (60%)
Opened fewer sites	4 (40%)
Missing	6

^aDesign not given in the protocol/proposal for 1 trial; unclear from the available information for 2 trials
^bNot given for 8 trials
^cSecond review involved revised recruitment targets; 1 trial underwent close monitoring alongside second review
^dNot applicable for 1 trial – no sites since recruitment takes place online
^eNumber of planned pilot sites not given for 12 trials
^fIncluding pilot sites; not given for 2 trials
IDSMC Independent Data and Safety Monitoring Committee, TSC Trials Steering Committee, TMG Trial Management Group

ISSN: 1745-6215