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Table 1 Applicability of recommend content of statistical analysis plans for clinical trials to observational studies

From: DEBATE-statistical analysis plans for observational studies

Section/Item Index Description for clinical trials Description for observational studies
Section 1: Administrative information
 Title and study registration 1a Descriptive title that matches the protocol, with SAP either as a forerunner or subtitle, and trial acronym Descriptive title that matches the protocol, with SAP either as a forerunner or subtitle, and study acronym
1b Trial registration number Study registration number
 SAP version 2 SAP version number with dates Unchanged
 Protocol version 3 Reference to version of protocol being used Unchanged
 SAP revisions 4a SAP revision history Unchanged
4b Justification for each SAP revision Unchanged
4c Timing of SAP revisions in relation to interim analyses, etc. Timing of SAP revisions in relation to planned repetitive analyses
 Roles and responsibility 5 Names, affiliations, and roles of SAP contributors Unchanged
 Signatures of: 6a Person writing the SAP Unchanged
6b Senior statistician responsible Unchanged
6c Chief investigator/clinical lead Unchanged
Section 2: Introduction
 Background and rationale 7 Synopsis of trial background and rationale including a brief description of research question and brief justification for undertaking the trial Synopsis of study background and rationale including a brief description of research question and brief justification for undertaking the study
 Objectives 8 Description of specific objectives and hypotheses Description of specific objectives and hypotheses, including secondary objectives
Section 3: Study methods
Study design 9 Brief description of trial design including type of trial (e.g. parallel group, multi-arm, crossover, factorial and allocation ratio and may include brief description of interventions) Brief description of study design including type of study (e.g. case-control, cross-sectional or cohort study)
Randomization 10 Randomization details, e.g., whether any minimization or stratification occurred (including stratifying factors used or the location of that information if it is not held within the SAP) Not applicable
Power considerations 11 Full sample size calculation or reference to sample size calculation in protocol (instead of replication in SAP) In case of an unspecified sample size, provide power calculations for (at least) the primary analysis or present a detectable difference with a specified power*
 Framework 12 Superiority, equivalence, or noninferiority hypothesis testing framework, including which comparisons will be presented on this basis Unchanged*
 Statistical repetitive analyses and stopping guidance 13a Information on interim analyses specifying what interim analyses will be carried out and listing of time points Information on repetitive analyses specifying what repetitive analyses will be carried out and listing of time points*
13b Any planned adjustment of the significance level due to interim analysis Any planned adjustment of the significance level due to repetitive analyses
13c Details of guidelines for stopping the trial early Details of guidelines for stopping the study early
 Timing of final analysis 14 Timing of final analysis, e.g., all outcomes analysed collectively or timing stratified by planned length of follow-up Unchanged*
 Timing of outcome assessments 15 Time points at which the outcomes are measured including visit “windows” Unchanged
Section 4: Statistical principles
 Confidence intervals and P-values 16 Level of statistical significance Unchanged*
17 Description and rationale for any adjustment for multiplicity and, if so, detailing how the type 1 error is to be controlled Unchanged*
18 Confidence interval to be reported Unchanged
 Adherence and protocol deviations 19a Definition of adherence to the intervention and how this is assessed including extent of exposure Not applicable
19b Description of how adherence to the intervention will be presented Not applicable
19c Definition of protocol deviations for the trial Definition of protocol deviations for the study
19d Description of which protocol deviations will be summarized Unchanged
 Analysis populations 20 Definition of analysis populations, e.g., intention to treat, per protocol, complete case, safety Definition of analysis populations, e.g., per protocol, complete case, safety
Section 5: Study Population
 Screening data 21 Reporting of screening data (if collected) to describe representativeness of trial sample Reporting of screening data (if collected) to describe representativeness of study sample
 Eligibility 22 Summary of eligibility criteria Unchanged
 Recruitment 23 Information to be included in the CONSORT flow diagram Information to be included in the STROBE flow diagram
 Withdrawal/follow-up 24a Level of withdrawal, e.g., from intervention and/or from follow-up Level of withdrawal, e.g., dropouts after inclusion or refusal to be contacted for additional information
24b Timing of withdrawal/lost to follow-up data Unchanged
24c Reasons and details of how withdrawal/lost to follow-up data will be presented Unchanged
 Baseline patient characteristics 25a List of baseline characteristics to be summarized Unchanged
25b Details of how baseline characteristics will be descriptively summarized Unchanged
Potential confounding covariates A description of potential confounding covariates and how these will be dealt with*
Section 6: Analysis
 Outcome definitions   List and describe each primary and secondary outcome including details of:  
26a Specification of outcomes and timings. If applicable include the order of importance of primary or key secondary end points (e.g., order in which they will be tested) Unchanged
26b Specific measurement and units (e.g., glucose control, HbA1c [mmol/mol or %]) Unchanged
26c Any calculation or transformation used to derive the outcome (e.g., change from baseline, QoL score, time to event, logarithm, etc) Unchanged
 Analysis methods 27a What analysis method will be used and how the treatment effects will be presented Unchanged*
27b Any adjustment for covariates Unchanged
27c Methods used for assumptions to be checked for statistical methods Unchanged
27d Details of alternative methods to be used if distributional assumptions do not hold, e.g., normality, proportional hazards, etc Unchanged
27e Any planned sensitivity analyses for each outcome where applicable Unchanged*
27f Any planned subgroup analyses for each outcome including how subgroups are defined Unchanged*
 Missing data 28 Reporting and assumptions/statistical methods to handle missing data (e.g., multiple imputation) Unchanged*
 Additional analyses 29 Details of any additional statistical analyses required, e.g. complier-average causal effect analysis Unchanged
 Harms 30 Sufficient detail on summarizing safety data, e.g. information on severity, expectedness, and causality; details of how adverse events are coded or categorized; how adverse event data will be analysed, i.e. grade ¾ only, incidence case analysis, intervention emergent analysis Only applies when interventions are studied. Sufficient detail on summarizing safety data, e.g. information on severity, expectedness, and associations; details of how adverse events are scored; how adverse event data will be analysed and the follow-up time.*
 Statistical software 31 Details of statistical packages to be used to carry out analysis Unchanged
 References 32a References to be provided for nonstandard statistical methods Unchanged
32b Reference to Data Management Plan Unchanged
32c Reference to the Trial Master File and Statistical Master File Reference to the Study Master File and Statistical Master File
32d Reference to other standard operation procedures to be adhered to Unchanged
  1. This table was adapted with permission from Gamble et al. [7]. Italic text highlights a rephrased word/sentence in the modified description for observational studies. An asterisk (*) indicates that a more elaborate description is present in our manuscript