as far as the aim of the study is concerned , the current research belongs to the  fundamental research category , and as the analytical methodology is concerned , it is a co - relational study , conducted to probe the relationship between ocss and negative /positive symptoms in schizophrenia . the statistical population of this study consisted of male / female schizophrenia admitted to iran psychiatry hospital from june 2010 to august 2010 . the sample group comprised of 31 schizophrenia with ocss ( 19men , 12women ) who were selected from the above - mentioned population through convenience sampling . all the subjects met the criteria for schizophrenia according to dsm - iv - tr by a psychiatrist , which was then confirmed by a clinical psychologist through structured clinical interview for dsm - vi - tr axis i disorders(scid - i)(21 ) . clients were assigned to different types of schizophrenia : 28 clients to the paranoid type , 2 to the undifferentiated type and 1 to the disorganized type . all the subjects were from 18 to 60 years old and had clinically significant ocss as confirmed by at least two psychiatrists . a clinical psychologist assessed the severity of ocss by using yale - brown obsessive - compulsive scale ( y - boc ) . outpatient subjects were stable and within the last month , no single changes in their prescribed medications were made . exclusion criteria were : 1 ) a history of past or current drug abuse or dependence ; 2 ) comorbid mood disorders ; 3 ) mental retardation ; 4 ) presence of extrapyramidal symptoms . the current study was conducted in outpatient clinic and the male and female wards of iran psychiatric hospital . subjects were selected based on convenience sampling model , then were interviewed , and they agreed to participate in the study . a minimum score of 8 on the y - bocs and minimum of six months duration of ocss were required for the diagnosis of clinically significant ocss . finally , positive and negative symptoms of schizophrenia were rated by a clinical psychologist using positive and negative syndrome scale ( panss ) . in order to maximize the accuracy of information , clients ' families were also interviewed . 
 the checklist of yale - brown obsessive - compulsive scale ( y - boc ) : the checklist presented is a part of the overall y - bocs scale which was invented by goodman and his collogues ( 22 ) . in this checklist , the score of zero ( 0 ) was assigned for lack of problems , ( 1 ) mild , ( 2 ) moderate , ( 3 ) severe , and ( 4 ) very severe . hence , by summing up the scores on all the five scales , a total score of 20 related to the client 's obsessions was gained . finally , based on the acquired score showing the degree of ocd , each client was categorized into one of four different levels , i.e. low ( 815 ) , moderate ( 1623 ) , severe ( 2431 ) , and very severe ( 32 - 40 ) . this scale enjoys an acceptable degree of validity and reliability in assessing the severity of obsessive symptoms ( 22 ) . evaluators reliability in 40 clients was 98% and internal consistency coefficient ( alpha coefficient ) was 89% ( 23 ) . in a study on 50 iranian clients , the degree of reliability of this scale , assessed through retest in two weeks time interval , has been reported to be 84% ( 24 ) . panss has 30 articles and 3 sub - scales of positive , negative , and general psychopathology for schizophrenia ( 25 ) . the consensus among evaluators for 31 clients with three sub - scales has been reported to be 0.83 , 0.85 , and 0.87 , respectively ; the consistency coefficient was also reported to be 0.73 , 0.83 , and 0.79 respectively ; and validity in a 3-to-6 month time period was 0.80 , 0.68 , and 0.60 for the three sub - scales ( 25 ) . the statistical population of this study consisted of male / female schizophrenia admitted to iran psychiatry hospital from june 2010 to august 2010 . the sample group comprised of 31 schizophrenia with ocss ( 19men , 12women ) who were selected from the above - mentioned population through convenience sampling . all the subjects met the criteria for schizophrenia according to dsm - iv - tr by a psychiatrist , which was then confirmed by a clinical psychologist through structured clinical interview for dsm - vi - tr axis i disorders(scid - i)(21 ) . clients were assigned to different types of schizophrenia : 28 clients to the paranoid type , 2 to the undifferentiated type and 1 to the disorganized type . all the subjects were from 18 to 60 years old and had clinically significant ocss as confirmed by at least two psychiatrists . a clinical psychologist assessed the severity of ocss by using yale - brown obsessive - compulsive scale ( y - boc ) . outpatient subjects were stable and within the last month , no single changes in their prescribed medications were made . exclusion criteria were : 1 ) a history of past or current drug abuse or dependence ; 2 ) comorbid mood disorders ; 3 ) mental retardation ; 4 ) presence of extrapyramidal symptoms . the current study was conducted in outpatient clinic and the male and female wards of iran psychiatric hospital . subjects were selected based on convenience sampling model , then were interviewed , and they agreed to participate in the study . a minimum score of 8 on the y - bocs and minimum of six months duration of ocss were required for the diagnosis of clinically significant ocss . finally , positive and negative symptoms of schizophrenia were rated by a clinical psychologist using positive and negative syndrome scale ( panss ) . in order to maximize the accuracy of information , clients ' families were also interviewed . 
 the checklist of yale - brown obsessive - compulsive scale ( y - boc ) : the checklist presented is a part of the overall y - bocs scale which was invented by goodman and his collogues ( 22 ) . in this checklist , the score of zero ( 0 ) was assigned for lack of problems , ( 1 ) mild , ( 2 ) moderate , ( 3 ) severe , and ( 4 ) very severe . hence , by summing up the scores on all the five scales , a total score of 20 related to the client 's obsessions was gained . finally , based on the acquired score showing the degree of ocd , each client was categorized into one of four different levels , i.e. low ( 815 ) , moderate ( 1623 ) , severe ( 2431 ) , and very severe ( 32 - 40 ) . this scale enjoys an acceptable degree of validity and reliability in assessing the severity of obsessive symptoms ( 22 ) . evaluators reliability in 40 clients was 98% and internal consistency coefficient ( alpha coefficient ) was 89% ( 23 ) . in a study on 50 iranian clients , the degree of reliability of this scale , assessed through retest in two weeks time interval , panss has 30 articles and 3 sub - scales of positive , negative , and general psychopathology for schizophrenia ( 25 ) . the consensus among evaluators for 31 clients with three sub - scales has been reported to be 0.83 , 0.85 , and 0.87 , respectively ; the consistency coefficient was also reported to be 0.73 , 0.83 , and 0.79 respectively ; and validity in a 3-to-6 month time period was 0.80 , 0.68 , and 0.60 for the three sub - scales ( 25 ) . panss has 30 articles and 3 sub - scales of positive , negative , and general psychopathology for schizophrenia ( 25 ) . the consensus among evaluators for 31 clients with three sub - scales has been reported to be 0.83 , 0.85 , and 0.87 , respectively ; the consistency coefficient was also reported to be 0.73 , 0.83 , and 0.79 respectively ; and validity in a 3-to-6 month time period was 0.80 , 0.68 , and 0.60 for the three sub - scales ( 25 ) . the subjects of the study consisted of 19 males ( 61.3 % ) and 12 females ( 38.7 % ) within the age range of 21 - 60 with the mean age of 33.06 years . as presented in table ( 1 ) , most of the subjects ( 15 ) were within the age range of 21 - 30 , and very few were within the age range of 51 - 60 . the mean and standard deviation of the variables are also presented in table ( 2 ) . as shown in this table , the mean of positive symptoms ( 23.878.16 ) is higher than the mean of negative symptoms ( 21.647.83 ) . the mean of compulsions ( 12.745.23 ) is also higher than the mean of obsessions ( 9.776.56 ) . 
  demographic information of schizophrenia clients with obsessive - compulsive symptoms ( ocss ) ( n = 31 ) based on the results of pearson correlation analysis ( table 2 ) , obsessions have a significant negative correlation with negative symptoms of clients with schizophrenia ( r = -0.424 ) . there is also a significant positive correlation between positive symptoms and negative symptoms of clients with schizophrenia . however , no significant correlation was found between compulsions and negative symptoms of schizophrenic clients . further , no significant correlation was observed between positive symptoms and compulsions and obsessions . the mean , standard deviation , and correlation coefficients of schizophrenia clients with obsessive - compulsive symptoms ( ocss ) in order to determine the role of ocss in the prediction of negative symptoms of schizophrenia , stepwise regression analysis was employed . as presented in the table 3 , of the two variables utilized in regression analysis , only obsessions significantly predicted negative symptoms ( ( =-0.424 , t = -2.52 , p = 0.017 ) the correlation coefficient of obsession symptoms and schizophrenia negative symptoms is 0.424 ; this variable is able to predict 18% of schizophrenia negative symptoms variance ( r = 0.18 ) . as a result , the findings are statistically meaningful . stepwise regression of schizophrenia negative symptoms based on obsessive and compulsive symptoms n=31 dependent variable : schizophrenia negative symptoms since no significant correlation was found between positive symptoms and obsessions and compulsions , using regression model to predict positive symptoms based on obsessive and compulsive symptoms does not seem logical . according to the findings of the current research , a significant negative relationship exists between obsessive symptoms and negative symptoms of schizophrenia . the results also showed that obsessive symptoms meaningfully predicted negative symptoms of schizophrenia . in the other words , as the obsessive symptoms increase , the negative symptoms of clients with schizophrenia decrease . this finding is in line with some prior studies , which showed presence of ocss with schizophrenia was associated with less negative symptoms ( 16 , 26 , 27 , and 6 ) . in a study on clients with first - episode schizophrenia ( 16 ) , the schizo - obsessive group showed lower scores in the flat affect subscale from the scale for the assessment of negative symptoms ( sans ) . in another study by this group ( 5 ) on hospitalized schizophrenia , it was reported that no significant relationship was observed between ocss and positive and negative symptoms of schizophrenia . they concluded that ocss have a protective effect on some schizophrenia symptoms in the early stages of the disorder , which fade away as the disorder advances . in one study schizophrenia with ocss showed fewer negative symptoms and had a better function compared to those schizophrenia without ocss . the authors reasoned that the fewer negative symptoms in these clients might reflect the higher scores in the scale for global assessment of functioning ( gaf ) ( 26 ) . higher scores in the quality of life scale ( qol ) in this group as compared to control group confirmed that ocss have a protective function in schizophrenia(6 ) . in some other studies , co - morbidity of schizophrenia and ocss exacerbated the severity of schizophrenia symptoms ( 28 , 29 , 14 and 4 ) . a possible explanation of such conflicting findings might be the existing difference in duration of the illness among the investigated subjects , which in turn has caused more negative symptoms and a poorer prognosis of schizo - obsessive clients in the more chronic clients . owashi 's study on the schizophrenia with duration of illness 34 years ) corroborates this tentative explanation ( 4 ) . the subjects of wetrel 's study consisted of middle - aged and elderly clients with chronic schizophrenia ( 29 ) . however , there were less negative symptoms in a sample group of clients with brief period of illness , and prognoses of the clients were better . as an example , the average age and duration of illness of subjects in tiboo 's study ( 26 ) were 35 and 6.8 years , respectively . apart from this group , subjects of poyurovsky 's study ( 16 ) were also clients with the first episode of psychosis . on a par with previous studies , findings of the present study might also be affected by the average age - range of subjects ( 33.06 ) and duration of the illness ( 9.54 ) . lysaker ( 30 ) , koo ( 31 ) , and owashi 's ( 4 ) findings revealed that more negative symptoms are observed in subjects with schizophrenia subjects with ocss . however , their findings are in direct contradiction to our results . such lack of harmony in findings might be due to the fact that the definition of ocss varied in different studies , which in turn could have led to more severe negative symptoms in those subjects with the diagnosis of ocd at high rates and fewer negative symptoms in those diagnosed as having less ocd ( 4 ) . based on the findings of this study , no significant relationship was found between ocss and schizophrenic positive symptoms , which are quite in line with previous extensive researches ( 32 , 5 , 17 , 18 , 8 , 33 and 19 ) . no significant relationships were found between ocss and positive / negative symptoms of schizophrenia , proving that ocss is independent of schizophrenia symptoms . on the other hand the sub - group of schizo - obsessive is probably a unique sub - group of schizophrenia ( 5 , 18 and 19 ) . our results are in contrast with some other studies in literature ( 13 , 15 , 7 , 14 ) , in which the presence of ocss in schizophrenia was associated with more positive symptoms . lack of agreement in the related literature might be due to the cross - sectional research designs employed on the one hand and the diversity of the sample groups ( chronic clients versus first - episode ) on the other ( 34 ) . the cross - sectional design of this study , and also lack of a comparison group , did not allow the researchers reach a conclusion regarding the outcome of the schizophrenia clients . since the evaluations and interviews conducted were the retrospective nature , it was possible that clients recalled information was biased . we could not investigate the duration of illness on severity of psychotic symptoms in schizo - obsessive clients . it is suggested that in the future studies , with employing a prospective design , first episode of schizophrenic clients to be evaluated . this study reveals that presence of obsessions in schizophrenia maintains the psychological function of the clients in dealing with course of the disorder . as a matter of fact , obsessions , reducing the negative symptoms , have a protective function in schizophrenia and do not necessarily cause a poorer prognosis . in addition , it seems that the co - occurrence of schizophrenia and ocss is related to a specific clinical picture , schizo - obsessive sub - type , which is a different sub - type from schizophrenia disorder . further studies are needed to evaluate the role of such factors as insight , anxiety , and depression on severity of ocss . it is advised that this study also be conducted on the subtypes of schizophrenia disorder .
objectivethe aim of the present study is to investigate the relationship between obsessive - compulsive symptoms ( ocss ) and negative and positive symptoms in schizophrenia.methodssubjects of the study comprised of 31 schizophrenia with obsessive - compulsive symptoms ( 19 men and 12 women ) selected by convenience sampling method from iran psychiatric hospital . 
 the diagnoses were established on the basis of dsm - iv - tr . 
 the required data were obtained using positive and negative syndrome scale ( panss ) and yale - brown obsessive - compulsive scale ( y - boc).resultsthe results of multiple regression analysis indicated that obsessive symptoms inversely predict negative symptoms . in other words , as the obsessive symptoms increase , the negative symptoms of schizophrenia decrease . 
 nevertheless , no significant relationship was found between ocss and positive symptoms.conclusionthis study reveals that ocss exert a protective effect on schizophrenia and do not necessarily cause poorer prognosis .