Psychometrics tutorial  General steps

View the accompanying screencasts: [1] [2]

Recommended psychometric instrument development steps emphasised in this tutorial are:
 Check and prepare the data
 Reverse code (if necessary) so that all variables are scored in the same direction
 Examine the univariate properties (e.g., histogram, mean, standard deviation, skewness, and kurtosis)
 Examine the bivariate properties (e.g., scatterplots and correlations) to help understand the data.
 Exploratory factor analysis
 Decide on a purpose and ask a research question
(e.g., what are the underlying dimensions of X?)
 Examine assumptions (sample size, linear relations, and factorability)
 Choose method of:
 Determine the number of factors
 Name and describe each factor
 Identify which items belong to each factor, drop problematic items as necessary, and repeat analysis
 Analyse internal consistency for each factor
 Examine correlations amongst the factors
 Compute composite scores (if needed)
 Check factor structure across subgroups
