Background: Schizophrenia has been described as the most disabling mental disorder, and patients with schizophrenia have been said to be disabled mostly in occupation, sexual relation, self-care, and social relationship domains.
Aim: The present study aimed at assessing disability through self-, proxy-, and interviewer-rated versions of the World Health Organization Disability Assessment Schedule (WHODAS) 2.0 among persons with schizophrenia.
Materials and Methods: The study was cross-sectional. Thirty samples of patients with schizophrenia as per the International Classification of Diseases-10 criteria were selected using a consecutive sampling technique. Patients above 18 years of age with a total duration of illness of at least more than 2 years were included in the study. The study was conducted at the Outpatient Department of Mental Health Institute and Department of Psychiatry, Government Medical College and Hospital Sector 32, Chandigarh, India.
Results: The overall inter-rater reliability in schizophrenia was 0.599 (0.395–0.767), indicative of moderate reliability. Domains, namely, getting along with people (0.803) and life activities of household (0.854) had a good reliability, whereas domains such as cognition (0.681), mobility (0.616), self-care (0.636), life activities at school/work (0.664), and participation in the society (0.753) indicated a moderate reliability.
Conclusion: There was no significant difference among the self, proxy, and interviewer assessments for most items. This study highlighted the fact that service users can also carry out an objective self-assessment of disability, thus upholding the principles of advanced directives as envisaged under the Mental Health Care Act, 2017.
Keywords: Disability, interviewer, proxy, schizophrenia, self, World Health Organization Disability Assessment Schedule 2.0
|How to cite this URL:|
Paul FA, Ali A. Disability assessment in the persons with schizophrenia: Inter-rater agreement and correlation between self-, proxy-, and interviewer-rated versions of the World Health Organization Disability Assessment Schedule 2.0. Arch Ment Health [Epub ahead of print] [cited 2023 Mar 24]. Available from: https://www.amhonline.org/preprintarticle.asp?id=365908
| Introduction|| |
Disability is defined as any restriction or degradation of an individual's expected functioning in a specific society caused by the family, social group, or the afflicted individual. As a result, social variables such as gender, unemployment, and family understanding of the nature of the illness may have an impact on the assessment and level of impairment in schizophrenia. In schizophrenia, disability has an impact on a person's psychological, social, and vocational functioning. Self-care, self-management, vocational and leisure activities, and social interactions are among the dimensions of a patient's daily life that are affected. Schizophrenia is a serious mental illness that affects many people around the world. It starts early in life, progresses through time, and has a significant impact on patients, their families, and society.,, Schizophrenia affects around 1% of the population, with a lifetime prevalence of 5.8%. It affects more than 21 million individuals around the globe and causes disability.
The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) was established by the WHO in 2010 and is based on the International Classification of Functioning, Disability, and Health (ICF). The WHODAS 2.0 is a systematic approach for evaluating physical and psychological difficulties related to mental diseases that have been proven to be effective (The American Psychiatric Association, 2014). The WHODAS 2.0 is directly linked to the ICF and examines disability and health status in the six domains of functioning: cognition, mobility, self-care, getting along with others, life activities, and participation. It is designed as a generic assessment of the level of disability experienced in activities that a person participates in and is directly linked to the ICF. Furthermore, the WHODAS is considered the best current assessment of disability for clinical use by the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition Task Force, which recommends that clinicians and researchers use the WHODAS instead of the Global Assessment of Functioning Scale to measure functional impairment. However, the WHODAS 2.0 has only been used in a few large-scale investigations to assess the level of impairment in schizophrenia patients.
Clinicians who are involved in the assessment and certification of disability for persons with mental illness have been experiencing difficulty in giving an exact percentage (%) of disability using IDEAS as it gives a range of disabilities and not an exact score. Other challenges to the use of IDEAS are also there (e.g., assessing disability in persons who stay alone). Despite having applicability across cultures, meager research has been done in India using the WHODAS 2.0. The scale holds immense potential for the future as it overcomes the limitation of IDEAS. The WHODAS 2.0 has three versions patient-rated, proxy-rated, and clinician-rated. As the Mental Health Care Act, 2017, emphasizes on rights perspective and gives importance to the view of service users, it is essential to see whether persons with mental illness can provide a proper self-assessment of their disability. Furthermore, by looking at the agreement between the patient-rated, proxy-rated, and clinician-rated versions, we may be able to know if these versions can act as proxy measures for the patients whenever they are not able to report their disability themselves and thus protect their human rights. To the best of the researcher's knowledge, till now, no such study has been conducted in the Indian population which has studied the disability through self-, proxy-, and interviewer-rated versions of the WHODAS 2.0. The present study aimed to assess disability, see the inter-rater reliability and correlation through self-, proxy-, and interviewer-rated versions of the WHODAS 2.0 among the persons with schizophrenia in India.
| Materials and methods|| |
The study was cross-sectional in nature. Thirty persons with schizophrenia were selected using a consecutive sampling procedure as per the International Classification of Diseases-10 (ICD-10) criteria. The researcher used the self-, proxy-, and interviewer-administrated versions of the WHODAS 2.0 (36 items). The study was conducted at the Outpatient Department (OPD) of the Mental Health Institute (MHI) and the Department of Psychiatry, Government Medical College and Hospital Sector 32, Chandigarh. Persons diagnosed with schizophrenia as per the ICD-10, aged above 18 years of age with a total duration of illness of at least 2 years were included. Those who refused to give written informed consent for the study were excluded. Thirty caregivers of these patients who were above 18 years of age, of any gender, willing to give written informed consent, General Health Questionnaire (GHQ) score <3, and studied up to 10th standard were included in the study. Ethical clearance was obtained from the Institutional Ethical Committee of GMCH, Chandigarh.
Instruments used in the study
Sociodemographic pro forma and clinical datasheet
This was a semistructured pro forma that was used to tap details such as age, gender, education level, marital status, type of family, occupation, religion, age of onset of illness, duration of illness, duration of treatment, and number of hospitalizations.
The World Health Organization Disability Assessment Schedule 2.0 (36-item self-, proxy-, and interviewer-administered questionnaire)
The WHODAS 2.0 36-item version is an assessment tool developed by the WHO to measure disability and functional impairment in accordance with the International Classification of Functioning, Disability, and Health. The WHODAS 2.0 measures average functioning in everyday situations for the past 30 days, and surveys six domains of functioning: (1) cognition (understanding and communicating), (2) mobility (ability to move and get around), (3) self-care (e.g., with regard to hygiene, dressing, and eating), (4) getting along with others, (5) life activities (ability to attend to everyday responsibilities), and (6) participation in the society.
The general health questionnaire-12
is a well-known and efficient tool for measuring the psychological morbidity in the respondents. It is used worldwide in different segments of practice and research – clinical, epidemiological, and psychological. It consists of 12 items with each item measuring the severity of mental health problems in the 4 weeks preceding the study. The scoring method (0-0-1-1) is used to sum up the points to a total score ranging between 0 and 12 with a higher score indicating a poorer mental health.
Capacity assessment guidance document by the Government of India
It is a guidance document developed by the Government of India, Ministry of Health and Family Welfare as per section 81 (1) of the Mental Healthcare Act, 2017, for assessing, when necessary, the capacity of a person to make mental health care or treatment decisions.
Thirty patients with a diagnosis of schizophrenia as per the ICD-10 criteria attending the OPD of MHI, and Department of Psychiatry, Government Medical College and Hospital Sector 32, Chandigarh, were approached for the study. For the patient group, first of all, a capacity assessment tool was administered. Patients who had the capacity to give written informed consent and fulfilled the selection criteria were included in the study. The patient's group was given the WHODAS 2.0 (36-item version self-administered) to rate their disability, and in case they had any queries while filling the questionnaire, they were provided help by the researcher. The caregivers (proxy) of the same patient were also approached for written informed consent. Those who gave consent and fulfilled inclusion and exclusion criteria were administered a sociodemographic datasheet and GHQ-12. Caregivers who had a GHQ-12 score equal to or more than 3 were excluded from the study and referred to the Psychiatry OPD for further evaluation. The caregivers who scored less than 3 were given the WHODAS 2.0 (36-item version proxy-administered) to rate their patient's disability. The researcher was available to help, in case patients or caregivers had any query regarding filling the questionnaire. In addition, the researcher also assessed the patient's disability independently using the WHODAS 2.0 (36-item version interviewer-administered). Before administering the WHODAS 2.0 scale, the researcher was provided an extensive training in the administration of the WHODAS 2.0 by the supervisors.
The purpose and the design of the study were explained to the patient and accompanying primary caregiver. The patient and the consenting family members were informed that they could withdraw at any time from the study without having to give reasons for the same. In any case, they would continue to receive an appropriate treatment for their condition. The confidentiality of the information obtained was maintained and was revealed only to doctors/auditors of this study. The defined guidelines of the Central Ethics Committee for Biomedical Research on human subjects by the ICMR were adhered to, in addition to the principles enunciated in the Declaration of Helsinki.
The data were statistically analyzed. The normality of quantitative data was checked by the measures of Kolmogorov–Smirnov tests of normality. Continuous data were reported as mean ± standard deviation. Categorical variables were reported as counts and percentages. Reliability analysis and analysis of variance were used to check the inter-rater reliability between the three raters (self, proxy, and interviewer) using inter-rater reliability analysis. Correlation (Pearson) was done between the three raters (self, proxy, and interviewer). All statistical tests were two-sided and performed at a significance level of α = 0.05. Analysis was conducted using SPSS program (Version 23.0; IBM Corporation, Armonk, NY, USA).
| Results|| |
[Table 1] shows the sociodemographic characteristics of schizophrenia patients (N = 30). The sample comprised predominantly of males (76.7%). Sixty percent of the samples were in the age range of 18–39 years. A majority of the samples were the followers of Hinduism (83.3%). Most of the patients were unmarried (76.7%), were from the nuclear family (76.7%), and hailed from the rural communities (63.3%). A majority of the samples were from the union territory of Chandigarh (50%) and were comfortable speaking the Hindi language (76.7%).
[Table 2] shows the clinical details of the patients with schizophrenia. Overall 80.0% had a long-standing illness of more than 5 years and also taken treatment for an illness of >5 years (80.0%). Most of the participant's age of onset of illness was in the age group of 18–30 years (76.7%). A majority of the patients neither had any family history of psychiatric illness (86.7%) nor were hospitalized from 1 to 5 times in their lifetime (80%).
[Table 3] shows the domain-wise inter-rater reliability of the WHODAS 2.0 in persons with schizophrenia. The overall inter-rater reliability in the schizophrenia group is 0.599 (0.395–0.767), indicative of moderate reliability. Domains, namely, getting along with people (0.803) and life activities of household (0.854) had a good reliability, whereas domains such as cognition (0.681), mobility (0.616), self-care (0.636), life activities at school/work (0.664), and participation in the society (0.753) indicated a moderate reliability.
|Table 3: The overall and domain-wise inter-rater reliability of the World Health Organization Disability Assessment Schedule 2.0 among persons with schizophrenia|
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[Table 4] shows that a significant difference in the schizophrenia group (P < 0.047) in the rating done by the patient and caregiver compared to the clinician rating was only seen in the “participation in the society” domain, and the rest of the domains did not show any significant difference.
|Table 4: Domain-wise mean, confidence interval, standard deviation, etc., score for different raters in schizophrenia|
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[Table 5] shows the inter-rater reliability which is expressed by intraclass correlation measures of the WHODAS 2.0. The majority of correlations between the WHODAS 2.0 self to the proxy was 0.457, proxy to the interviewer was 0.499, and self to the interviewer was 0.541. Strong correlations were observed between self to proxy and proxy-to-interviewer raters.
|Table 5: Inter-rater correlations of the World Health Organization Disability Assessment Schedule 2.0 scores among schizophrenia|
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| Discussion|| |
The 36-Item Version of the WHODAS 2.0 has suitable psychometric properties in terms of reliability and validity when applied to the patients with schizophrenia. The overall inter-rater reliability among self-, proxy-, and interviewer-rated versions of the WHODAS 2.0 in the schizophrenia group came out to be 0.599 (0.395–0.767), indicative of a moderate reliability. The domains that had a good reliability were getting along with people (0.803) and life activities of household (0.854), whereas domains that exhibited a moderate reliability were cognition (0.681), mobility (0.616), self-care (0.636), life activities at school/work (0.664), and participation in the society (0.753). The findings are similar to one of the previous studies done by. It highlights that the overall degree of disability in schizophrenia patients was moderate compared to other mental illness. One of the studies conducted by, where the findings of the research study highlight that the degree of disability in schizophrenia patient's cognition domain was moderate, which supports the finding of the present study where patients with severe mental illness exhibit deficits on a diverse set of information-processing functions. There is ample evidence for a generalized or executive deficit as well as focal impairments in specific functions such as memory and attention. In another study done by Garin et al. 2010, at Taipei, the result highlights that in the mobility domain, the inter-rater reliability was mild compared to the present study; it was contradictory as patient reports that they fear going outside alone, thus restricting mobility.
In the present study, there was no significant difference among the self, proxy, and interviewer assessments for most items on the WHODAS 2.0. However, a significant difference (P < 0.047) was seen in the domain of “participation in the society, wherein the self and proxy who were administered the WHODAS 2.0 gave lesser scores, respectively, compared to the interviewer. The “participation in the society” domain addresses the patient's feelings about the society's view of their disease as well as the impact of their illness on their families. The evidence is suggestive that stigma impacts not only the patients suffering from mental illness but also people who are closely related to them like family, friends, and relatives. Schizophrenia has received much attention in stigma, and it is one of the most disabling and stigmatizing of mental illness. However, the majority experiencing “disability in the participation in the society” domain is not a new finding; it may be a reflection of the patient's difficulty in initiating and maintaining social relationships., The possible reasons for this may be emotional blunting and apathy being experienced in schizophrenia, which may make sufferers not appreciate the relationship needs and expectations of others.
Persons with schizophrenia continue to face stigma, social exclusion, discrimination, and violation of their human rights in the country as well as around the globe. This is mainly due to the myths, misconceptions, and cultural beliefs associated with mental illness. They are robbed of opportunities for quality of life and purposeful interaction in their communities, with family members, relatives, and friends. Participation is regarded as crucial to a person's well-being and quality of life. A majority of the participants in the present study were from the rural areas where mental illness is still stigmatized, and such persons were perceived differently by the society; this may be the reason for high scores in the clinician-rated version of the WHODAS 2.0 in the domain of “participation in the society.” These findings are comparable to another study, where they highlighted that stigmatization is higher in the rural areas. Persons with schizophrenia have a lack of insight and cognitive impairment. This may influence self-perception on some of the items where an insight could help understand the response process in disability scales.
Patients with severe mental illness and their caregivers had a moderate degree of agreement when assessing the six domains of the WHODAS 2.0. A few studies that compared patient and proxy ratings in the WHODAS 2.0 administration in patients with schizophrenia have similar findings. Studies report that the caregivers are likely to provide quite similar ratings to those of the patients even when moderate correlations are found. Therefore, the finding that agreement between self and proxy is sufficiently good, would suggest that substituting patient scores with proxy/caregivers scores is possible. These findings are comparable to one of the previous studies conducted by Kim et al., in Seoul, South Korea.
The present study highlights the importance of assessing disability in persons with schizophrenia through self, proxy, and interviewer-rated versions of the WHODAS 2.0. Which gives scope for patients to assess their own disabilities. According to the Mental Health Care Act, of 2017, the patient has the capacity to assess his or her disability using the self-administered version. As per the Mental Health Care Act, 2017, it is mentioned that there is a right of the patient in the form of advance directives and also to choose the treatment facilities. Interviewer rating typically assesses disability and activity restriction. It gives information regarding a specific behavior observed and is less vulnerable to psychosocial influences, but it is restricted in that a small sample of seen behavior may result in an underestimation of a patient's capacity.
Strength and limitations of the study
This study had many strengths such as only clinically stable patients were induced in the study, stringent inclusion and exclusion criteria were followed, all ethical considerations were well taken care of, and what made it unique is that to the best knowledge of the researcher, it is the first such study in India that checked the persons with schizophrenia through self-, proxy-, and interviewer-rated versions of the WHODAS 2.0 in the Indian settings. A major limitation of this study is that it was conducted in only a single hospital. However, other limitations were also identified like small sample size; potential bias cannot be ruled out as the rater was not blinded to the diagnosis of the participants; and finally, the study participants were restricted to a specific diagnosis, namely, schizophrenia, who visited a clinical facility which could limit the generalization of the result.
| Conclusion|| |
Disability is quite common among persons with schizophrenia, albeit in the mild to moderate variety. Most patients have the greatest difficulty in forming social relationships and having difficulty participating in the society domain. Thus, it can be concluded that the overall inter-rater reliability of the WHODAS 2.0 among the self, proxy, and interviewer versions was moderate with no significant difference among the self, proxy, and interviewer assessments for most items. This upholds the principle of advance directives as articulated by the MHCA, 2017, that gives the right persons with mentally ill having the capacity to take treatment-related decisions, thereby increasing the self-reliance of the patient and their caregivers in access to health care.
The authors would like to thank all of the people who participated in the study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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Fayaz Ahmad Paul,
Department of Psychiatric Social Work, LGB Regional Institute of Mental Health, Tezpur, Assam
Source of Support: None, Conflict of Interest: None
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]