These results display data about the cross-cultural adapted to the English version of the BrP-MQOL-R. The process of translating and back translating the English BrP-MQOL-R to the Brazilian Portuguese translation was carried out stringently following established guidelines. (9) The set of questions of the BrP-MQOL-R presented satisfactory internal reliability with Cronbach's alpha coefficients higher than 0.85, likewise to the original English version. Our findings indicated an adequate construct validity and internal consistency of the BrP-MQOL-R translated and adapted to Brazilian Portuguese. (9) They also showed that the items with higher load are those related to social and psychosocial, and the lowest was found in the physical domains.
The content validity is evidenced by the high scores of the questionnaire items for readability, clarity, and comprehensiveness, as demonstrated by the scores on the visual analog scale in the assessment of the expert's committee consulted. Likewise, the result was found in a sample of patients in palliative care. This process yielded a Brazilian Portuguese version of MQOL-R semantically equivalent to the English language MQOL-R. Thus, the current version of the BrP-MQOL-R can be used without significant difficult in Portuguese-speaking populations. The test for internal consistency by Cronbach's alfa indicates that either in the items and domains showed adequate consistency among their responses (see Table 2, 3). These internal consistency coefficients by Cronbach's alpha are like them obtained original scale. (8)
CFA of the BrP-MQOL-R using a variety of different goodness of-fit model measures indicate an adequate construct validity. Like the original version, the model shows the goodness of fit with four factors: Existential, Social, Psychological, and Physical. (8) The CFA demonstrated that all items of four factors showed a load factorial higher than 0.4. This result indicates that all elements of each factor converge to a common point to constitute a construct. Thus, our result confirms how well our analyzed variables represent the original constructs. (8) A strength of BrP-MQOL-R is items in each of the four subscales remain as proposed by Robin Cohen and colleagues. (8) The CFA suggests that it is possible to maintain the original structure scale items in the BrP-MQOL-R. Also, the factor analysis supports using separate scores for each one of the four domains.
We found moderate correlations between several domains, indicating that the experience in one life domain is related to other domains. Further, to examine the convergence validity of BrP-QOL-R, we analyzed the strength of the relationship with the functional status by KPS score and in the SIS about the quality of life. All correlation coefficients among these factors were less than 0.5 (see Table 4).
According to literature, the correlation for concurrent validity measure comparable concepts could not exceed 0.7.(19) Thus, the weak association of the MQOL-R summary score with an SIS QOL (r = .33) suggests that BrP-MQOL-R measure QOL in a related, but not the identical way. While the SIS assesses the QOL in a unidimensional way, the global score of BrP-MQOL-R evaluates the quality of life from a multidimensional way. As expected, the conversely and weak correlation of the QOL score and the subscales indicates the sensibility of these measures to identify the negative impact of pain on the quality of life. They also support improving educational programs to improve pain management since it impacts the global quality of life.
The relevance of these results is to evidence that the BrP-MQOL-R showed a sensibility identify the effect of factors that contribute to worst QOL either cancer or non-cancer patients. For example, the pain level, which is a specific aspect of healthcare, is a person-centered experience. Is sum, these findings demonstrated that this tool validated and adapted to the Brazilian population is suitable as part of an assessment of "quality of life" in patients in palliative care. Another measure that showed the theoretical construct of the BrP-MQOL-R is the criterion-validity to differentiate those patients unable to perform their activities with or without assistance compared to those that need medical care but less than the distinguished group. Thus, this intensive process to establish the validity of the BrP-MQOL-R provided reliable support for its validity in more depth. Thereby, we can offer the Brazilian population an instrument to assess the quality of life" in palliative care adequately adapted. This is important to clinical and for research from a transcultural perspective. Notably, it would be a useful tool to evaluate how the impact of support pharmacological and non-pharmacological in palliative care in different cultures. Mainly because in patients under palliative care, the illnesses are in progress, and healthcare takes on an increasingly important role day by day in these people's life. Hence, the quality of life should be the most target in the care of these patients.
In the present study, males were associated with the worst quality of life compared to females. Accordingly, to prior research investigating sex differences in aggressiveness of end of life care preferences (20) and women are less likely to prefer life-sustaining technology and other aggressive treatments. Also, they are more likely to give do-not-resuscitate orders to have a dignified death. (20) While another survey found that among patients with advanced cancer, women were more likely than men to recognize that their disease was incurable and at an advanced stage and report having discussed life expectancy with their oncologist. (21) Another result that evidenced the discriminatory properties of the validated scale was identifying the worst quality of life of patients in the hospital compared to patients in palliative care at home. This finding is plausible and supported by earlier surveys conducted in the United States (US), the UK, and the Netherlands, which reported that the quality of the end of life in hospitals was not satisfactory. (22–24)
The main limitations of this study should be addressed. First, the test-retest was not performed. However, it is important to realize that the reliability of the test-retest gives more reliable results when a patient's health status is stable at both times of the test. (25) In the context of palliative care, the clinical status changes faster sometimes in hours or in a few days at the way that this measure would be less reliable. Second, the study is limited by the nonrandom selection of patients recruited in palliative care service at a university hospital. Hence, selection bias is possible, and it is uncertain whether these findings can be extrapolated to patients receiving treatment in hospitals without palliative care. However, it is noteworthy that our results are consistent with findings observed in the original English language version, which involved a variety of a representative national sample. (26) Third, the study is based on self-report measures. Thus, the comprehension of items content of the assessment instruments may have implications for the internal validity of the survey. Finally, longitudinal studies are required with a more significant number of clinical samples.