It was found that clinical trials in schizophrenia are likely to utilize the PANSS for psychopathology as well as the set of AIMS, BARS and SAS for EPS assessment. Overall frequency in the assessment scales for schizophrenia in an effort to evaluate multiple domains within the illness appeared to be similar across years, except for more recent attention on cognition, functioning and subjective perspectives. The PANSS together with the set of AIMS, BARS and SAS may be regarded as ‘the standard’ in clinical trials for schizophrenia. This ‘standard’ set of assessment scales is expected to take about 60 minutes (30–40/5–10/10/10 minutes for the PANSS/AIMS/BARS/SAS, respectively).2 Such a time requirement obviously represents an obstacle for real-world practice.
Studies have utilized different scales for their different interests and we can not be entirely certain about which scales are adequate in a specific study. It is important to acknowledge that all assessment scales do have some pertinence across multiple illness domains. Furthermore, contrary to the naming, the QLS for example was designed to assess deficit symptoms and can well be regarded as a functional outcome measure in schizophrenia. On the other hand, an interpretation of clinical relevance on improvements in a part of the scales, or in subscales within the scale, remains somewhat complex although such a data presentation is sometimes found to focus on statistically significant differences.
Limitations of this paper include a limited number of years and studies investigated and an arbitrary classification of outcomes into domains. Outcome measures may be in part guided by the nature of the study (e.g., pharmacologic versus psychosocial) or the setting (e.g., real-world versus research). The year of publication (or tradition) of each rating scale is also an important factor since rating scales would require some time to become familiarized with (and years that accompany the citations serve to have a sense of the ‘age’ of the scales). Challenges with the existing rating scales are discussed below.