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Table 4 Data we will extract to allow calculation of effect sizes

From: Management of UK priority invasive alien plants: a systematic review protocol

Data to extractDescription of data
Treatment meanMean value for outcome in area/time period subject to management intervention
Control meanMean value for outcome in area/time period not subject to management intervention
Treatment standard deviation (SD)Standard deviation for outcome in area/time period subject to management intervention
Control standard deviation (SD)Standard deviation value for outcome in area/time period not subject to management intervention
Treatment NSample size for outcome in area/time period subject to management intervention
Control NSample size in area/time period not subject to management intervention
Treatment standard error (SE)Standard error for outcome in area/time period subject to management intervention
Control standard error (SE)Standard error value for outcome in area/time period not subject to management intervention
UnitUnits used to measure outcome (e.g.  %, Kg ha−1, or number of stems ha−1)
Least Significant Difference (LSD)Metric allowing determination of statistical significance of a comparison between treatment mean and control mean
Correlation coefficient (r)Measure of linear correlation between two variables (Pearson correlation coefficient)
Total N for correlation studiesTotal sample size for studies that calculated the Pearson correlation coefficient
Approximate P valueApproximate P value where exact value of P is not given
Exact P valueExact P value where it is given in the study
Exact Z valueExact Z value where it is given in the study
Exact F valueExact F value where it is given in the study. F values will only be taken from non-omnibus tests (i.e. not ANOVA tests) because these allow us to determine pairwise statistical significance