Differentiating subtypes of bulimia nervosa: examining the differences between subjective and objective bingers

The purpose of this investigation was to examine whether differences exist between bulimics exhibiting predominantly subjective binge behavior and bulimics exhibiting primarily objective binge behavior on several measures of psychopathology. The specific measures of interest in this study were average caloric intake across binge episodes, binge frequency, and purge frequency. This study replicates aspects of previous research attempts to examine differences in psychopathology between subjective and objective bingers, with the notable exception that the sampling procedure did not require participants to meet the DSM-IV diagnostic criteria for bulimia nervosa. Instead, participants were admitted to the subjective binge group if they met all DSM-IV diagnostic criteria for bulimia nervosa except criterion A(1), which specifies that a binge episode must consist of a large amount of food. Participants were admitted to the objective binge group if they met all DSM-IV diagnostic criteria for bulimia nervosa. It was hypothesized that members comprising the subjective binge group would display lower average caloric binge intake, higher binge frequency, and higher purge frequency. Conversely, it was predicted members of the subjective binge group would display higher average caloric binge intake, lower binge frequency, and lower purge frequency. Two cluster analyses were performed to explore whether the hypothesized subgroups were present in the data. The first cluster analysis, performed using Ward\u27s method, yielded the two predicted subjective and objective groupings, as well as two additional groups. The second cluster analysis, performed using the average linkage method, produced four similar groupings, including two groups with characteristics similar to those expected to be present among subjective and objective bingers. Implications of the findings and directions for further research are discussed