TREND Statement Checklist

Paper 

Section/

Topic

Item 

No

Descriptor Reported?

Pg #

Title and Abstract

Title and 

Abstract

1 Information on how unit were allocated to interventions

Structured abstract recommended

Information on target population or study sample

Introduction

Background 2 Scientific background and explanation of rationale

Theories used in designing behavioral interventions

Methods

Participants 3 Eligibility criteria for participants, including criteria at different levels in 

recruitment/sampling plan (e.g., cities, clinics, subjects)

Method of recruitment (e.g., referral, self-selection), including the 

sampling method if a systematic sampling plan was implemented

Recruitment setting

Settings and locations where the data were collected

Interventions 4 Details of the interventions intended for each study condition and how 

and when they were actually administered, specifically including:

o Content: what was given?

o Delivery method: how was the content given?

o Unit of delivery: how were the subjects grouped during delivery?

o Deliverer: who delivered the intervention?

o Setting: where was the intervention delivered?

o Exposure quantity and duration: how many sessions or episodes or 

events were intended to be delivered? How long were they 

intended to last?

o Time span: how long was it intended to take to deliver the 

intervention to each unit?

o Activities to increase compliance or adherence (e.g., incentives)

Objectives 5 Specific objectives and hypotheses

Outcomes 6 Clearly defined primary and secondary outcome measures

Methods used to collect data and any methods used to enhance the 

quality of measurements

Information on validated instruments such as psychometric and biometric 

properties

Sample Size 7 How sample size was determined and, when applicable, explanation of any 

interim analyses and stopping rules

Assignment 

Method

8 Unit of assignment (the unit being assigned to study condition, e.g., 

individual, group, community)

Method used to assign units to study conditions, including details of any 

restriction (e.g., blocking, stratification, minimization)

Inclusion of aspects employed to help minimize potential bias induced due 

to non-randomization (e.g., matching)
TREND Statement Checklist

Blinding 

(masking)

9 Whether or not participants, those administering the interventions, and 

those assessing the outcomes were blinded to study condition assignment; 

if so, statement regarding how the blinding was accomplished and how it 

was assessed.

Unit of Analysis 10 Description of the smallest unit that is being analyzed to assess 

intervention effects (e.g., individual, group, or community)

If the unit of analysis differs from the unit of assignment, the analytical 

method used to account for this (e.g., adjusting the standard error 

estimates by the design effect or using multilevel analysis)

Statistical 

Methods

11 Statistical methods used to compare study groups for primary methods 

outcome(s), including complex methods of correlated data

Statistical methods used for additional analyses, such as a subgroup 

analyses and adjusted analysis

Methods for imputing missing data, if used

Statistical software or programs used

Results

Participant flow 12 Flow of participants through each stage of the study: enrollment, 

assignment, allocation, and intervention exposure, follow-up, analysis (a 

diagram is strongly recommended)

o Enrollment: the numbers of participants screened for eligibility, 

found to be eligible or not eligible, declined to be enrolled, and 

enrolled in the study

o Assignment: the numbers of participants assigned to a study 

condition

o Allocation and intervention exposure: the number of participants 

assigned to each study condition and the number of participants 

who received each intervention

o Follow-up: the number of participants who completed the followup or did not complete the follow-up (i.e., lost to follow-up), by 

study condition

o Analysis: the number of participants included in or excluded from 

the main analysis, by study condition

Description of protocol deviations from study as planned, along with 

reasons

Recruitment 13 Dates defining the periods of recruitment and follow-up

Baseline Data 14 Baseline demographic and clinical characteristics of participants in each 

study condition

Baseline characteristics for each study condition relevant to specific 

disease prevention research

Baseline comparisons of those lost to follow-up and those retained, overall 

and by study condition

Comparison between study population at baseline and target population 

of interest

Baseline 

equivalence

15 Data on study group equivalence at baseline and statistical methods used 

to control for baseline differences
TREND Statement Checklist

Numbers 

analyzed

16 Number of participants (denominator) included in each analysis for each 

study condition, particularly when the denominators change for different 

outcomes; statement of the results in absolute numbers when feasible

Indication of whether the analysis strategy was “intention to treat” or, if 

not, description of how non-compliers were treated in the analyses

Outcomes and 

estimation

17 For each primary and secondary outcome, a summary of results for each 

estimation study condition, and the estimated effect size and a confidence 

interval to indicate the precision

Inclusion of null and negative findings

Inclusion of results from testing pre-specified causal pathways through 

which the intervention was intended to operate, if any

Ancillary 

analyses

18 Summary of other analyses performed, including subgroup or restricted 

analyses, indicating which are pre-specified or exploratory

Adverse events 19 Summary of all important adverse events or unintended effects in each 

study condition (including summary measures, effect size estimates, and 

confidence intervals)

DISCUSSION

Interpretation 20 Interpretation of the results, taking into account study hypotheses, 

sources of potential bias, imprecision of measures, multiplicative analyses, 

and other limitations or weaknesses of the study

Discussion of results taking into account the mechanism by which the 

intervention was intended to work (causal pathways) or alternative 

mechanisms or explanations

Discussion of the success of and barriers to implementing the intervention, 

fidelity of implementation

Discussion of research, programmatic, or policy implications

Generalizability 21 Generalizability (external validity) of the trial findings, taking into account 

the study population, the characteristics of the intervention, length of 

follow-up, incentives, compliance rates, specific sites/settings involved in 

the study, and other contextual issues

Overall 

Evidence

22 General interpretation of the results in the context of current evidence 

and current theory

From: Des Jarlais, D. C., Lyles, C., Crepaz, N., & the Trend Group (2004). Improving the reporting quality of 

nonrandomized evaluations of behavioral and public health interventions: The TREND statement. American Journal of 

Public Health, 94, 361-366. For more information, visit: http://www.cdc.gov/trendstatement/