Subjective evaluation: is there more than one criterion?

Previous cross-sectional investigations have shown that subjective evaluation criteria (criteria that are used in psychiatric research for evaluating care based on patients' statements) do overlap and that there exists a single general factor underlying all these criteria. In this study, we tested longitudinally and in two different samples of schizophrenia patients the distinctness and covariation at baseline and at followup of three common subjective evaluation criteria (subjective quality of life, self-rated needs, and self-reported symptoms). Scores were intercorrelated at both baseline and followup and showed some intercorrelations over time, suggesting temporal covariation. One stable subjective appraisal factor was identified at both baseline and followup, summarizing a negative subjective quality of life and more symptoms and needs. This factor explained 50 percent to 69 percent of the variance. It was found to be strongly associated with observer-rated mood and was mainly predicted by reporting dark thoughts and being dissatisfied with life as a whole. In subjective evaluation, there appears to be a need to distinguish between a general appraisal factor and specific aspects of different criteria. Therefore, future research needs to focus on how the general factor can be assessed more directly and to identify how the specific variance of different criteria independent of that factor can be maximized.