Response styles and shared method variance
If respondents exhibit habitual response styles when answering self-reported survey questions, this can present risks to the accuracy of the responses and any subsequent analyses that explore relationships between variables. One of the key risks associated with response styles is that, by introducing a relatively stable bias across several self-reported variables, they can artificially inflate correlations between those variables - a phenomenon often described in the literature as shared or common method variance. This is a particular problem for cross-sectional analyses of survey data. With longitudinal or panel data, it is possible to eliminate the impact of stable response styles (i.e. fixed effects) by focusing instead on which variables are able to predict changes in responses over time.
The section below briefly reviews the relatively rare studies that have attempted to actually measure and quantify specific response styles and considers some of the evidence regarding the extent to which response styles present a particular problem for subjective well-being data. Some illustrations of the problem of shared method variance are also provided. Implications for data analysis and interpretation are discussed at greater length in Chapter 4.