a sample of 103 voluntary male participants , based on their response to the following question from the whoqol - bref questionnaire :  are you currently ill ?
( yes - no )  , were divided into two groups : unhealthy ( n=55 ) and healthy ( n=48 ) respectively . 

whoqol - bref and the depression anxiety stress scale ( dass-42 ) were used to assess satisfaction rating and negative emotions of depression , anxiety and stress .
the who 's qol scale ( whoqol - bref ) was used to assess satisfaction with four domains of life : physical health , psychological , social relationships and environment support .
the four domain scores are scaled in a positive direction , with a score range of 0 - 20 , and with higher scores denoting higher satisfaction .
the 42-item format of dass was used to measure the negative emotional states of depression , anxiety and stress . in order to find how rating the whoqol - bref and dass scales is combined to produce an overall measure of quality of life and satisfaction with health rating , a qol - dass model was designed ; and the strength of this hypothesized model of qol - dass
was examined using structural equation modeling ( figure 1 ) . in this model , ellipses represent latent variables ; whoqol , and dass , and rectangles represent measured variables ; satisfaction in four different domains of life , physical health , psychological well - being , social relations , and environment , as measured with whoqol - bref and depression , anxiety , stress as measured with dass-42 .
a sample of 103 voluntary male participants , based on their response to the following question from the whoqol - bref questionnaire :  are you currently ill ?
( yes - no )  , were divided into two groups : unhealthy ( n=55 ) and healthy ( n=48 ) respectively .

 whoqol - bref and the depression anxiety stress scale ( dass-42 ) were used to assess satisfaction rating and negative emotions of depression , anxiety and stress .
the who 's qol scale ( whoqol - bref ) was used to assess satisfaction with four domains of life : physical health , psychological , social relationships and environment support .
the four domain scores are scaled in a positive direction , with a score range of 0 - 20 , and with higher scores denoting higher satisfaction .
the 42-item format of dass was used to measure the negative emotional states of depression , anxiety and stress .
in order to find how rating the whoqol - bref and dass scales is combined to produce an overall measure of quality of life and satisfaction with health rating , a qol - dass model was designed ; and the strength of this hypothesized model of qol - dass was examined using structural equation modeling ( figure 1 ) . in this model , ellipses represent latent variables ; whoqol , and dass , and rectangles represent measured variables ; satisfaction in four different domains of life , physical health , psychological well - being , social relations , and environment , as measured with whoqol - bref and depression , anxiety , stress as measured with dass-42 .
for analysis , a confirmatory factor analysis ( cfa),using maximum likelihood , was conducted on a sample of 103 participants whose scores derived from two rating scales of whoqol - bref and dass-42 . using amos and maximum likelihood estimation
, the relationships were examined between the whoqol , a latent variable with 4 indicators of four domains concerning with satisfaction with physical health ( dom1 ) , psychological well - being ( dom2 ) , social relationships ( dom3 ) and environment support ( dom4);and another latent variable , dass , with 3 indicators of depression , anxiety , and stress ratings .
the most commonly used goodness - of - life index is the chi - square statistic .
the results of the run of the data obtained from the proposed model of qol - dass is presented in table 1 . 
 
fit indices of the model of qol - dass for different healthy and unhealthy groups = chi - square ; df= degrees of freedom ; cfi= comparative fit index ; nnfi= non - normed fit index ; nfi= normed fit index ; rmsea = root mean square error of approximation ; pclose = probability of close fit as observed in table 1 , for both the healthy and unhealthy groups , the 2 statistic for the proposed model of qol - dass indicates that the proposed model fit the data well , which seemed to suggest an inadequate fit of the model . moreover , other indicators indicated much more favorable results . 

table 2 provides estimated regression weights ( b ) and standardized regression weight (  ) coefficients of all pathways for the hypothesized model of qol - dass . 
 
regression weights ( b ) and standardized regression weight (  ) coefficients in order to find whether or not components of the measurement model ( qol - dass model ) are invariant across particular groups ( here scores are derived from healthy and unhealthy persons),a multiple group analysis was conducted on the two groups .
these groups varied depending on their response to a question (  do you feel ill now ?-
the  no  response for the healthy group ; and the  yes  response for the unhealthy group .
the question is whether the relation between specific items ( satisfaction with physical health ( dom1 ) , psychological well - being ( dom2 ) , social relationships ( dom3 ) , environment support ( dom4 ) , depression , anxiety , and stress ratings . ) and the underlying construct or factor ( whoqol and dass ) tapped by the item is the same across groups .
unconstrained  model does not specify any constraints on groups of healthy and unhealthy participants , and the  measurement weights  model specifies all the factor loadings as equal on the different studied groups .
fit indices as well as the change in 2 , and change in degrees of freedom between  unconstrained  and  measurement weights  models are presented in table 3 . 
 
goodness - of - fit statistics for tests of invariance across different groups cfi= comparative fit index ; rmsea = root mean square error of approximation as demonstrated in table 3 , the comparison of models , unconstrained and measurement weights , was found to be non - significant across healthy / unhealthy groups ( 2 = 7.95 , df = 9 , ns . given this finding
, it can be concluded that the factor loading is shown invariant across the studied groups .
in order to find whether or not components of the measurement model ( qol - dass model ) are invariant across particular groups ( here scores are derived from healthy and unhealthy persons),a multiple group analysis was conducted on the two groups .
these groups varied depending on their response to a question (  do you feel ill now ?-
the  no  response for the healthy group ; and the  yes  response for the unhealthy group .
the question is whether the relation between specific items ( satisfaction with physical health ( dom1 ) , psychological well - being ( dom2 ) , social relationships ( dom3 ) , environment support ( dom4 ) , depression , anxiety , and stress ratings . ) and the underlying construct or factor ( whoqol and dass ) tapped by the item is the same across groups .
unconstrained  model does not specify any constraints on groups of healthy and unhealthy participants , and the  measurement weights  model specifies all the factor loadings as equal on the different studied groups .
fit indices as well as the change in 2 , and change in degrees of freedom between  unconstrained  and  measurement weights  models are presented in table 3 . 
  goodness - of - fit statistics for tests of invariance across different groups cfi= comparative fit index ; rmsea = root mean square error of approximation as demonstrated in table 3 , the comparison of models , unconstrained and measurement weights , was found to be non - significant across healthy / unhealthy groups ( 2 = 7.95 , df = 9 , ns . given this finding
, it can be concluded that the factor loading is shown invariant across the studied groups .
george & bearon , ( 16 ) , define quality of life in terms of four underlying dimensions , two of which are objective ( general health and functional status and socioeconomic status ) and two of which reflect the personal judgment of the individual ( life satisfaction and related measures and self - esteem and related measures ) , and believe that these dimensions are especially central for assessment of quality of life of older people ( 16 ) . although the boundary between subjective and objective components of qol is not always clear in practice , measures of quality of life are based on both objective and subjective variables ( 17 ) .
meeberg ( 1 ) referring to subjective and objective components of quality of life , claimed that the subjective aspect is essential because a sense of personal satisfaction is intrinsic to qol and the objective component is also necessary .
a person living in poverty and squalor who has never known any other way of life may feel satisfied with his or her life . yet
, a person from outside those living conditions can see the prevailing health hazards and would evaluate that individual 's qol as less than ideal ( 1 ) . in order to find how subjective evaluation of satisfaction with life domains and feeling negative emotions affect perceived general health and quality of life , a hypothesized model of qol - dass was designed , and the strength of this hypothesized model was examined using structural equation modeling ( see fig .
our results of running the hypothesized model of qol - dass indicated that the proposed model of qol - dass fitted the data well for both healthy and unhealthy groups ( see table 1 ) .
we continued our analysis by testing for multiple group invariance to find whether or not components of the measurement model , qol - dass model , are invariant across the two groups .
our results of conducting multiple group invariance across the groups of healthy and unhealthy indicate that all factor loadings across different groups used to be invariant ( table 3 ) . as the baseline ( unconstrained ) and
regression weights models are not significantly different , it is concluded that the hypothesized model of qol - dass is invariant between the two groups .
our findings to evaluate the hypothesized model of qol - dass indicate that the different satisfaction domain ratings obtained from whoqol - bref and the negative emotions ( depression , anxiety and stress measured using dass-42 as the observed variables ) can represent the underlying constructs of general health and quality of life on both healthy and unhealthy groups .
 objectivein order to find how rating the whoqol - bref and dass scales are combined to produce an overall measure of quality of life and satisfaction with health rating , a qol - dass model was designed ; and the strength of this hypothesized model was examined using the structural equation modeling.methodparticipants included a sample of 103 voluntary males who were divided into two groups of unhealthy ( n=55 ) and healthy ( n=48 ) . to assess satisfaction and negative emotions of depression , anxiety and stress among the participants , 
 they were asked to fill out the whoqol - bref and the depression anxiety stress scale ( dass-42).resultsour findings on running the hypothesized model of qol - dass indicated that the proposed model of qol - dass fitted the data well for the both healthy and unhealthy groups.conclusionour findings with cfa to evaluate the hypothesized model of qol - dass indicated that the different satisfaction domain ratings and the negative emotions of depression , anxiety and stress as the observed variables can represent the underlying constructs of general health and quality of life on both healthy and unhealthy groups . 
Materials and Method
Participants
Instruments
Statistical Analyses
Results
Testing for multiple group invariance
Discussion