[Scale for assessing negative symptoms in schizophrenia: A systematic review]

Area of Science:

• Psychiatry
• Clinical Psychology
• Neuroscience

Background:

• Negative symptoms are a core dimension of schizophrenia, impacting quality of life.
• Despite their significance, international diagnostic classifications have limited focus on negative symptoms.
• Several standardized assessment scales exist, though a consensual definition is still evolving.

Purpose of the Study:

• To identify unidimensional instruments for assessing negative symptoms in schizophrenia.
• To characterize these instruments, including their general features and included items.
• To evaluate their suitability for clinical practice.

Main Methods:

• Systematic review of unidimensional negative symptom assessment scales for schizophrenia.
• Inclusion criteria: unidimensional scales, English language (French versions preferred), all available instruments up to February 2013.
• Data extraction focused on scale characteristics, domains assessed, and administration requirements.

Main Results:

• Twelve unidimensional instruments were identified, with only one (MAP-SR) being self-administered.
• Scale length varied from 6 (SDS) to 25 items (SANS), with administration times from 5-10 minutes (HEN) to 30 minutes (SANS).
• The SANS assessed the most domains (11), while MAP-SR covered the fewest (3); emotional blunting, alogia, social withdrawal, anhedonia, and avolition were most frequently assessed.

Conclusions:

• Older instruments like SANS and NSA-16 are complex to administer.
• Newer scales such as BNSS and CAINS offer improved usability.
• While self-report (MAP-SR) is valuable, current options cover limited negative symptom domains; integrated patient self-report tools are needed.