#1. Statistical Tests for Different Types of Research Questions Knowing what type of research question your study is asking can often determine what statistical analysis to use. Some types of research questions are: Descriptive: Describing a sample or a population Comparing groups: Testing for differences between two or more groups. The statistical analysis used can depend on whether the groups come from different samples (independent), or the same samples tested at different time points (paired). Associations: Examining the relationships or links between two constructs of interest. Predictive: Does increasing (or decreasing) the value on one measure effect the value of another measure. Statistical Decision Table Based on Goal of Research Study Type of Data Measurement (from Binomial (Two Possible Goal Gaussian Population) Outcomes) Describe one group Mean, SD Proportion One-sample Chi-square or Binomial test** Compare one group to a ttest hypothetical value Compare two unpaired Unpaired test Fisher's test (chi-square for t groups large samples) Compare two paired groups Paired test McNemar's test t Compare three or more One-way ANOVA Chi-square test unmatched groups Compare three or more Repeated-measures ANOVA Cochrane Q** matched groups Pearson correlation Contingency coefficients** Quantify association between two variables Predict value from another Simple linear regression or Simple logistic regression* Nonlinear regression measured variable Multiple linear regression* or Multiple logistic regression* Predict value from several measured or binomial variables Multiple nonlinear regression** Statistical “Review Of Available Tests”
#1. Statistical Tests for Different Types of Research Questions Knowing what type of research question your study is asking can often determine what statistical analysis to use. Some types of research questions are: Descriptive: Describing a sample or a population Comparing groups: Testing for differences between two or more groups. The statistical analysis used can depend on whether the groups come from different samples (independent), or the same samples tested at different time points (paired). Associations: Examining the relationships or links between two constructs of interest. Predictive: Does increasing (or decreasing) the value on one measure effect the value of another measure. Statistical Decision Table Based on Goal of Research Study Type of Data Goal Measurement (from Gaussian Population) Binomial (Two Possible Outcomes) Describe one group Mean, SD Proportion Compare one group to a hypothetical value One-sample ttest Chi-square or Binomial test** Compare two unpaired groups Unpaired t test Fisher's test (chi-square for large samples) Compare two paired groups Paired t test McNemar's test Compare three or more unmatched groups One-way ANOVA Chi-square test Compare three or more matched groups Repeated-measures ANOVA Cochrane Q** Quantify association between two variables Pearson correlation Contingency coefficients** Predict value from another measured variable Simple linear regression or Nonlinear regression Simple logistic regression* Predict value from several measured or binomial variables Multiple linear regression* or Multiple nonlinear regression** Multiple logistic regression* “Review Of Available Statistical Tests”