Measuring negative symptom change in schizophrenia: considering alternatives to self-report

Abstract

Treatment of negative symptoms in schizophrenia is a priority, but is approaching stagnation, due in part to the methods used to assess change in these symptoms. Traditional methods for assessing negative symptoms employ subjective self-report and/or clinician-rated scales, both of which are contaminated by considerable measurement error. The purpose of this article is to highlight the limitations in current assessment measures for negative symptoms and discuss the advantages of quantitative objective measurement, particularly in the context of clinical trial research. Recent research from psychology, neuroscience and computer technology has produced objective quantitative measures such as facial analysis and virtual reality that are more precise and sensitive to change; these objective measures are poised to revolutionize the measurement of this critical symptom.

A meta-analytic review of self-reported, clinician-rated, and performance-based motivation measures in schizophrenia: Are we measuring the same “stuff”?

“…Only two studies were eligible to be included in the meta-analysis examining this relationship, and the effects in these studies were in opposite directions. Considering that prior studies have questioned the validity and reliability of self-reported measures for people with schizophrenia (Gupta, Holshausen, Gou, & Bowie, 2014; Takeuchi, Fervaha, & Remington, 2016) and several researchers have pointed to the need for additional psychometric evaluation studies of performance-based motivation measures (Barch, Gold, & Kring, 2017; Reddy et al, 2015), future studies are needed to more conclusively validate these measures in schizophrenia samples and understand the level of overlap in the underlying construct(s) that both self-reported and performance-based motivation measures are assessing.…”

“…The IMI-SR has gained notable traction, in part because it was one of the first non-negative symptom (i.e., amotivation) measures of motivation to be validated in a schizophrenia sample. Further, although some have expressed concerns about obtaining reliable data on self-reported measures from people with schizophrenia (Gupta, Holshausen, Gou, & Bowie, 2014; Takeuchi, Fervaha, & Remington, 2016), others have posited that because intrinsic motivation reflects internal states (i.e., the enjoyment one derives from an activity or the reason behind completing an activity), intrinsic motivation can only be truly measured with a self-reported measure (J. Choi et al, 2014; Kremen et al, 2016).…”

Systematic Literature Review of Studies Reporting Measures of Functional Outcome or Quality of Life in People with Negative Symptoms of Schizophrenia

“…For example, it may be difficult to delineate primary versus secondary NSS 1 and there may be potential for inter-observer variability in terms of quantifying NSS, although this may be reduced with training. 6 NSS can have a detrimental effect on everyday life and have been linked to poor quality of life (QoL) and impaired functional outcomes. 7,8 Functional outcomes include activities of daily living, social relationships and QoL 9 and a greater severity of NSS has been linked with worse functional outcomes.…”

“…For example, it may be difficult to delineate primary versus secondary NSS 1 and there may be potential for inter-observer variability in terms of quantifying NSS, although this may be reduced with training. 6 …”