Addi van Bergen

Supplementary material chapter 2 161 Supplementary file 2: CASP risk of bias tool for cross-sectional studies CASP Critical Appraisal Skills Programme 11 questions to help you make sense of descriptive/cross-sectional studies How to use this appraisal tool Three broad issues need to be considered when appraising the report of a descriptive/ cross-sectional study (e.g., a study that collects data on individuals at one time point using a survey or review of medical charts): • Are the results of the study valid? • What are the results? • Will the results help locally? The 11questions on the followingpages are designed tohelpyou think about these issues systematically. The first two questions are screening questions and can be answered quickly. If the answer to both is “yes”, it is worth proceeding with the remaining questions. You are asked to record a “yes”, “no” or “can’t tell” to most of the questions. A number of italicized prompts are given after each question. These are designed to remind you why the question is important. Record your reasons for your answers in the spaces provided. These questions are adapted from Guyatt GH, Sackett DL, and Cook DJ, Users’ guides to the medical literature. II. How to use an article about therapy or prevention. JAMA 1993; 270 (21): 2598-2601 and JAMA 1994; 271(1): 59-63 © Milton Keynes Primary Care Trust 2002. All rights reserved. Screening Questions 1. Did the study address a clearly focused issue? Yes Can’t tell No HINT: A question can be focused in terms of: • the population(s) studied • the health measure(s) studied (e.g., risk factor, preventive behavior, outcome) 2. Did the authors use an appropriate method Yes Can’t tell No to answer their question? HINT: Consider • Is a descriptive/cross-sectional study an appropriate way of answering the question? • Did it address the study question?