Neurological soft signs in schizophrenia: a meta-analysis
- PMID: 19377058
- PMCID: PMC2963054
- DOI: 10.1093/schbul/sbp011
Neurological soft signs in schizophrenia: a meta-analysis
Abstract
Background: Neurological soft signs (NSS) are hypothesized as candidate endophenotypes for schizophrenia, but their prevalence and relations with clinical and demographic data are unknown. The authors undertook a quantification (meta-analysis) of the published literature on NSS in patients with schizophrenia and healthy controls. A systematic search was conducted for published articles reporting NSS and related data using standard measures in schizophrenia and healthy comparison groups.
Method: A systematic search was conducted for published articles reporting data on the prevalence of NSS in schizophrenia using standard clinical rating scales and healthy comparison groups. Meta-analyses were performed using the Comprehensive Meta-analysis software package. Effect sizes (Cohen d) indexing the difference between schizophrenic patients and the healthy controls were calculated on the basis of reported statistics. Potential moderator variables evaluated included age of patient samples, level of education, sample sex proportions, medication doses, and negative and positive symptoms.
Results: A total of 33 articles met inclusion criteria for the meta-analysis. A large and reliable group difference (Cohen d) indicated that, on average, a majority of patients (73%) perform outside the range of healthy subjects on aggregate NSS measures. Cognitive performance and positive and negative symptoms share 2%-10% of their variance with NSS.
Conclusions: NSS occur in a majority of the schizophrenia patient population and are largely distinct from symptomatic and cognitive features of the illness.
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                References
Appendix II: Studies Included in Meta-analysis
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    - Arango C, Bartko JJ, Gold JM, Buchannan RW. Prediction of neuropsychological performance by neurological signs in schizophrenia. Am J Psychiatry. 1999;156:1349–1357. - PubMed
 
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    - Aydemir C, Goka E, Kisa C, Kurt A, Yuksel FV. Dyskinesia and soft neurological signs in schizophrenia: a comparative study. Int J Psychiatry Clin Pract. 2005;9:238–243. - PubMed
 
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    - Bachmann S, Bottmer C, Schröder J. Neurological soft signs in first-episode schizophrenia: a follow-up study. Am J Psychiatry. 2005;162:2337–2343. - PubMed
 
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    - Bersani G, Orlandi V, Gherardelli S, Pancheri P. Cannabis and neurological soft signs in schizophrenia: absence of relationship and influence on psychopathology. Psychopathology. 2002;35:289–295. - PubMed
 
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    - Biswas P, Malhotra S, Malhotra A, Gupta N. Comparative study of neurological soft signs in schizophrenia with onset in childhood, adolescence. Acta Psychiatr Scand. 2007;115:295–303. - PubMed
 
References
- 
    - Heinrichs RW, Zakzanis KK. Neurocognitive deficit in schizophrenia: a quantitative review of the evidence. Neuropsychology. 1998;12:426–445. - PubMed
 
- 
    - de Wilde OM, Bour LJ, Dingermans PM, Koelman JHTM, Linszen DH. A meta-analysis of the P50 studies in patients with schizophrenia and relatives: differences in methodology between research groups. Schizophr Res. 2007;97:137–151. - PubMed
 
- 
    - Heinrichs DW, Buchanan RW. The significance and meaning of neurological signs in schizophrenia. Am J Psychiatry. 1988;145:11–18. - PubMed
 
- 
    - Tsuang MT, Gilberson MW, Faraone SV. The genetics of schizophrenia: current knowledge and future directions. Schizophr Res. 1991;4:157–171. - PubMed
 
- 
    - Tsuang MT, Faraone SV. The concept of target features in schizophrenia research. Acta Psychiatr Scand Suppl. 1999;395:2–11. - PubMed
 
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