The UCSD Performance-based Skills Assessment - Brief version (UPSA-B) describes the functions of patients without negative influences of environmental factors such as unemployment or shortage in housing. The aim of the present study is to further explore the psychometric properties of the UPSA-B as well as to ensure that the Swedish version can be used in clinical practice and for research purposes. Participants were 211 patients, 135 men and 76 women, diagnosed with schizophrenia, schizoaffective disorder, or delusional disorder. Results indicate that the UPSA-B is a reliable instrument with good psychometric properties regarding validity and reliability. The instrument also had a capacity to reveal differences between various patient groups, both diagnostic groups and groups based on remission status. The conclusion drawn is that the UPSA-B is a valuable instrument that could be used in future cross-national studies to describe the level of functioning for patients with schizophrenia and other psychotic illnesses.

Schizophrenia is a severe disorder that often causes impairments in major areas of functioning, and most patients do not achieve expected real-world functional milestones. The aim of this study was to identify which variables of demography, illness activity, and functional capacity predict patients' ability to attain real-world functional milestones. Participants were 235 outpatients, 149 men and 86 women, diagnosed with schizophrenia spectrum disorder. Our results showed that younger patients managed to achieve a higher level of functioning in educational level, marital status, and social contacts. Patients' functional capacity was primarily associated with educational level and housing situation. We also found that women needed less support regarding housing and obtained a higher level of marital status as compared with men. Our findings demonstrate the importance of considering current symptoms, especially negative symptoms, and remission stability over time, together with age, duration of illness, gender, educational level, and current functional capacity, when predicting patients' future real-world functioning. We also conclude that there is an advantage in exploring symptoms divided into positive, negative, and general domains considering their probable impact on functional achievements.

People with schizophrenia often demonstrate an impaired ability to assess and report aspects of their everyday functioning, and the aim of this study is to investigate how patients' self-rating ability regarding functional performance relates to neurocognitive performance and real-world functional performance. A total of 222 outpatients with a schizophrenia spectrum disorder participated in this study. They were divided into groups based on their self-rating ability (determined using self-rating questions) and their observed functional capacity (the UCSD Performance-Based Skills Assessment-Brief, UPSA-B). The results showed that patients with impaired functional capacity perform at a similar cognitive level, regardless of their self-rating ability. When comparing patients with unimpaired function to those with impaired function, we found differences in two cognitive domains; premorbid functioning and executive functioning. The results also reveal that clinicians seem to have greater difficulty assessing patients who over-estimate their functioning. Consequently, when clinicians assessed the patients with the Specific Levels of Functioning Scale (SLOF) no significant differences were found between the group with unimpaired function and the group of overestimators. Patients who overestimate their functioning risk receiving inadequate treatment and support.