A randomised trial of adaptive pacing therapy, cognitive behaviour therapy, graded exercise, and specialist medical care for chronic fatigue syndrome (PACE): statistical analysis plan.
BACKGROUND
The publication of protocols by medical journals is increasingly becoming an accepted means for promoting good quality research and maximising transparency. Recently, Finfer and Bellomo have suggested the publication of statistical analysis plans (SAPs).The aim of this paper is to make public and to report in detail the planned analyses that were approved by the Trial Steering Committee in May 2010 for the principal papers of the PACE (Pacing, graded Activity, and Cognitive behaviour therapy: a randomised Evaluation) trial, a treatment trial for chronic fatigue syndrome. It illustrates planned analyses of a complex intervention trial that allows for the impact of clustering by care providers, where multiple care-providers are present for each patient in some but not all arms of the trial.


RESULTS
The trial design, objectives and data collection are reported. Considerations relating to blinding, samples, adherence to the protocol, stratification, centre and other clustering effects, missing data, multiplicity and compliance are described. Descriptive, interim and final analyses of the primary and secondary outcomes are then outlined.


CONCLUSIONS
This SAP maximises transparency, providing a record of all planned analyses, and it may be a resource for those who are developing SAPs, acting as an illustrative example for teaching and methodological research. It is not the sum of the statistical analysis sections of the principal papers, being completed well before individual papers were drafted.


BACKGROUND
ISRCTN54285094 assigned 22 May 2003; First participant was randomised on 18 March 2005.
MH&N Clinical Trials Unit, Institute of Psychiatry, King's College London, DeCrespigny Park, London SE5 8AF, UK. R.E.A.Walwyn@leeds.ac.uk.
Rebecca
R
Walwyn
Laura
L
Potts
Paul
P
McCrone
Anthony L
AL
Johnson
Julia C
JC
DeCesare
Hannah
H
Baber
Kimberley
K
Goldsmith
Michael
M
Sharpe
Trudie
T
Chalder
Peter D
PD
White
D000222:Adaptation, Physiological; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D003131:Combined Modality Therapy; D003362:Cost-Benefit Analysis; D003625:Data Collection; D005081:Exercise Therapy / Q000379:methods*; D015673:Fatigue Syndrome, Chronic / Q000628:therapy*; D006801:Humans; D017063:Outcome Assessment, Health Care; D012107:Research Design; D018401:Sample Size