Front page
Handbook information
Part 1: Cochrane reviews
Part 2: General methods for Cochrane reviews
    5 Defining the review question and developing criteria for including studies
    6 Searching for studies
    7 Selecting studies and collecting data
       7.1 Introduction
       7.2 Selecting studies
       7.3 What data to collect
       7.4 Sources of data
       7.5 Data collection forms
       7.6 Extracting data from reports
       7.7 Extracting study results and converting to the desired format
          7.7.1 Introduction
          7.7.2 Data extraction for dichotomous outcomes
          7.7.3 Data extraction for continuous outcomes
             7.7.3.0 Introductory text
             7.7.3.1 Post-intervention versus change from baseline
             7.7.3.2 Obtaining standard deviations from standard errors and confidence intervals for group means
             7.7.3.3 Obtaining standard deviations from standard errors, confidence intervals, t values and P values for differences in means
             7.7.3.4 Transformations and skewed data
             7.7.3.5 Medians and interquartile ranges
             7.7.3.6 Ranges
             7.7.3.7 No information on variability
             7.7.3.8 Combining groups
             Table7.7.a: Formulae for combining groups
          7.7.4 Data extraction for ordinal outcomes
          7.7.5 Data extraction for counts
          7.7.6 Data extraction for time-to-event outcomes
          7.7.7 Data extraction for estimates of effects
       7.8 Managing data
       7.9 Chapter information
       7.10 References
    8 Assessing risk of bias in included studies
    9 Analysing data and undertaking meta-analyses
    10 Addressing reporting biases
    11 Presenting results and 'Summary of findings' tables
    12 Interpreting results and drawing conclusions
Part 3: Special topics
Additional material