Item | Criterion | n (%) | |
Title and abstract | 1a | Term ‘pilot’ or ‘feasibility’ included in the title Identification as a pilot or feasibility randomised trial in the title | 15 (83) 12 (67) |
1a | Term ‘cluster’ included in the title Identification as a cluster randomised trial in the title | 12 (67) 12 (67) | |
Introduction | 2a [S] | Scientific background and explanation of rationale for future definitive trial reported Reasons for randomised pilot trial reported | 18 (100) 7 (39) |
2a | Rationale given for using cluster design | 6 (33) | |
Methods—trial design | 3a | Description of pilot trial design | 18 (100) |
3a | Definition of cluster | 18 (100) | |
3b | Reported any changes to methods after pilot trial commencement If yes, reported reasons | 5 (28) 5/5 (100) | |
Methods—participants | 4a | Reported eligibility criteria for participants | 13 (72) |
4a | Reported eligibility criteria for clusters | 9 (50) | |
4b | Reported settings and locations where the data were collected | 18 (100) | |
4 c [N] | Reported how participants were identified Reported how clusters were identified Reported how participants were consented * Reported how clusters were consented | 9 (50) 6 (33) 13/17 (76) 2 (11) | |
Methods—interventions | 5 | Described the interventions for each group | 13 (72) |
Methods—outcomes | 6b | Reported any changes to pilot trial assessments or measurements after pilot trial commencement If yes, reported reasons | 1 (6) 1/1 (100) |
6 c [N] | Reported criteria used to judge whether, or how, to proceed with the future definitive trial | 3 (17) | |
Methods—sample size | 7a [S] | Reported a rationale for the sample size of the pilot trial | 8 (44) |
7a | Cluster design considered during the description of the rationale for numbers in the pilot trial | 3 (17) | |
7b | Reported stopping guidelines | 0 (0) | |
Methods— randomisation | 8a | Reported method used to generate the random allocation sequence | 9 (50) |
8b | Reported randomisation method | 13 (72) | |
9 | Reported mechanism used to implement the random allocation sequence Reported allocation concealment | 4 (22) 7 (39) | |
10/ 10a | Reported who: Generated the random allocation sequence Enrolled clusters Assigned clusters to interventions | 8 (44) 3 (17) 4 (22) | |
10c | Reported from whom consent was sought Reported whether consent was sought from participants Reported whether consent was sought from clusters Reported whether participant consent was sought before or after randomisation* | 2 (11) 17 (94) 2 (11) 8/17 (47) | |
Methods— blinding | 11a | Reported on whether there was blinding Reported who was blinded† Reported how they were blinded† | 10 (56) 6/14 (43) 1/14 (7) |
Methods— analytical methods | 12a | Reports clustering accounted for in any of the methods used to address pilot trial objectives/research questions‡ | 13/17 (76) |
Results—participant flow | 13§ | Reports a diagram with flow of individuals through the trial | 12 (67) |
13§ | Reports a diagram with flow of clusters through the trial | 10 (56) | |
13a/ 13a [S] | Reported number of: Individuals (clusters) approached and/or assessed for eligibility¶ Individuals (clusters) randomly assigned¶ Individuals (clusters) that received intended treatment¶; ¶ Individuals (clusters) that were assessed for primary objective¶; ¶ | 8/17 (47); 10/18 (56) 13/17 (76); 17/18 (94) 8/17 (47); 5/17 (29) 16/17 (94); 14/17 (82) | |
13b/ 13b | Reported number of: Losses for individuals (clusters) after randomisation**; ¶ Exclusions for individuals (clusters) after randomisation¶; ¶ | 11/16 (69); 6/17 (35) 1/17 (6); 3/17 (18) | |
14a | Reported on dates defining the periods of recruitment Reported on dates defining the periods of follow-up | 8 (44) 11 (61) | |
14b | Reported the pilot trial ended/stopped | 0 (0) | |
Results—baseline data | 15 | Reported a table showing baseline characteristics for the individual level If yes, by group | 12 (67) 11/12 (92) |
15 | Reported a table showing baseline characteristics for the cluster level If yes, by group | 2 (11) 2/2 (100) | |
Results—outcomes and estimation | 17a | Reported results for main feasibility objective (quantitative or qualitative)†† | 13/17 (76) |
Results— harms | 19 | Reported on harms or unintended effects | 4 (22) |
19a [N] | Reported other unintended consequences | 0 (0) | |
Discussion | 20 [S] | Reported limitations of pilot trial Reported sources of potential bias Reported remaining uncertainty | 17 (94) 10 (56) 10 (56) |
21 [S] | Reported generalisability of pilot trial methods/findings to future definitive trial or other studies | 16 (89) | |
22 | Interpretation of feasibility consistent with main feasibility objectives and findings†† | 12/17 (71) | |
22A [N] | Reported implications for progression from the pilot to the future definitive trial | 16 (89) | |
Other information | 23 | Reported registration number for pilot trial Reported name of registry for pilot trial | 11 (61) 11 (61) |
24 [S] | Reported where the pilot trial protocol can be accessed | 7 (39) | |
25 | Reported source of funding | 18 (100) | |
26 [N] | Reported ethical approval/research review committee approval If yes, reported reference number | 17 (94) 8/17 (47) |
Item numbers in normal font refer to the item in the CONSORT extension for pilot trials that the quality assessment item is based on.
Item numbers in bold italics refer to the item in the CONSORT extension for CRTs that the quality assessment item is based on.
[N] represents new items in the CONSORT extension for pilot trials compared with the CONSORT 2010 for RCTs.
[S] represents items in the CONSORT extension for pilot trials that are substantially adapted from the CONSORT 2010 for RCTs.
*Item not relevant for one trial [A12] because they said that the Ethics Board determined it could be conducted without informed consent from patients or surrogates.
†Item not relevant for four trials [A7, A10, A12, A18] because they reported that blinding was not used.
‡Item not relevant for one trial because no CIs/p values were given, [A17] so clustering did not need to be accounted for in any of their methods because effect estimates are not biased by cluster randomisation, only CIs/p values.
§The CONSORT statements do not include an item 13 but there is a participant flow subheading which strongly recommends a diagram. We therefore reference this subheading as ‘item 13’ here.
¶Not relevant for one trial due to the design of the study.[A10] (This paper was different from the others such that it was not relevant to extract these items. The clusters were postcode areas and they were assessing two online recruitment interventions and comparing the success of the recruitment interventions. As such, participants were those who completed the online questions, and each arm of the study had a ‘total population ranging from 1.6 to 2 million people clustered in four postcode areas’.)
**Not relevant for two trials due to the design of these studies.[A10, A12] (See reason above for A10. For A12, data were collected from medical patient charts so these items were not relevant to extract.)
††One paper reports the feasibility results in a separate paper so is not included.[A3]