Prevalence of mixed-methods sampling designs in social science research

The purpose of this mixed-methods study was to document the prevalence of sampling designs utilised in mixed-methods research and to examine the interpretive consistency between interpretations made in mixed-methods studies and the sampling design used. Classification of studies was based on a two-dimensional mixed-methods sampling model. This model provides a typology in which sampling designs can be classified according to the time orientation of the components (i.e. concurrent versus sequential) and the relationship of the qualitative and quantitative samples (i.e. identical versus parallel versus nested versus multilevel). A quantitative analysis of the 42 mixed-methods studies that were published in the four leading school psychology journals revealed that a sequential design using multilevel samples was the most frequent sampling design, being used in 40.5% (n=17) of the studies. More studies utilised a sampling design that was sequential (66.6%; n=28) than concurrent (33.4%; n=14). Also, multilevel sampling designs were the most prevalent (54.8%; n=23), followed by identical sampling (23.8%; n=10), nested sampling (14.3%; n=6) and parallel sampling (7.1%; n=3). A qualitative analysis suggested a degree of interpretive inconsistency in many studies.