Abstract:

BACKGROUND: Meta-analysis or system evaluation theory and method of grouping design pattern comparison are mature. However, there are a few articles or methods for univariate relationship, single group outcome variable and their relationship.
OBJECTIVE: To introduce several effect statistics, such as pooled incidence rate estimates and pooled arithmetic means estimates used for noncomparative studies, mean gain effect sizes estimates used for pre-post contrasts studies.
METHODS: A computer-online search of the full text database of Chinese CNKI, VIP full text database of Chinese Doctoral database, Pubmed database was performed. Relevant meta-analysis or systematic review methodology literature about non-comparative studies and pre-post contrasts studies were included.
RESULTS AND CONCLUSION: Univariate described several common statistics, such as mean, median, mode or ratio, while Meta analysis analyzed ratio and mean (arithmetic mean). Pre-post contrasts studies is to explore the measurement of one variable of one group population (single sample) at two time points. This type of study is also called matched-pairs design mean comparison. Two effective size indexes can be selected in this study: non-standardized mean score and standardized mean score. If one measurement method is used for results variables of Meta analysis, non-standardized mean score can be used, otherwise, standardized mean score should be used as effect size.