Hypoalbuminaemia and its association with disease and clinical outcomes in cats.

OBJECTIVES: To report the incidence of feline hypoalbuminaemia and characterise the distribution of presenting disease categories and pathoaetiologies of hypoalbuminaemia in cats. The secondary aim was to evaluate the relationship between hypoalbuminaemia and clinical outcomes. MATERIALS AND METHODS: Medical records of cats with hypoalbuminaemia (<28.0 g/L, reference interval: 28.0 to 39.0 g/L) presenting to a veterinary teaching hospital over 5 years were retrospectively reviewed. The severity of hypoalbuminaemia was further stratified into mild (24.0 to 27.9 g/L), moderate (20.0 to 23.9 g/L) and severe (≤19.9 g/L) groups. The median albumin and severity groups were compared between the determined disease categories, pathoaetiologies and clinical outcomes. RESULTS: The incidence of hypoalbuminaemia was 32.7% (533/1632). Gastrointestinal disease was the most common disease category associated with hypoalbuminaemia [154/533 (28.9%)], of which, 49.4% (76/154) of cats had gastrointestinal neoplasia. Neoplastic [159/533 (29.8%)] and inflammatory conditions [158/533 (29.6%)] were common pathoaetiologies noted. Statistically significant differences in the serum albumin between individual disease and pathoaetiological categories were found. Cats with moderate to severe hypoalbuminaemia had a statistically significantly longer hospitalisation period, cost of treatment and increased odds of death (odds ratio 2.4, 95% confidence interval: 1.3 to 4.6 and odds ratio 3.2, 95% confidence interval: 1.5 to 6.6, respectively). CLINICAL SIGNIFICANCE: The incidence of feline hypoalbuminaemia in our study surpasses previous canine reports. Our findings support albumin as a negative acute phase protein in cats, with hypoalbuminaemia frequently associated with inflammatory disease. Hypoalbuminaemia also features prominently in cats with gastrointestinal neoplasia, indicating careful appraisal of the presence of protein-losing enteropathy is required in these cases. Finally, albumin is found to be a prognostic indicator in this study.

Impact of COVID-19 on environmental services workers in healthcare settings: a scoping review.

BACKGROUND: In the wake of the coronavirus disease 2019 (COVID-19) pandemic, demand for deep cleaning and environmental services workers grew exponentially. Although there is extant literature examining the impact of the COVID-19 pandemic on healthcare workers, less emphasis has been placed on environmental services workers, who play an equally important front-line role. AIM: To examine the impact of the COVID-19 pandemic on environmental services workers employed in healthcare settings. METHODS: Scoping review methodology. A search strategy was developed, in consultation with a medical information specialist, employing various combinations of the keywords [(environmental services worker OR health attendant OR housekeeping) AND (COVID OR coronavirus OR pandemic OR epidemic)]. Four bibliographical databases were searched from inception to 5th July 2022: OVID Medline, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Cochrane Database. RESULTS: In total, 24 studies were included in this review. The studies were generally cross-sectional in design. Seroprevalence studies highlighted significantly higher rates of COVID-19 among environmental services workers (housekeeping, cleaning and janitorial staff) compared with other clinical and non-clinical staff in the same institutions. In addition, based on qualitative interviews, environmental services workers experienced greater psychological stress working during the pandemic. CONCLUSIONS: Environmental services workers were particularly vulnerable to increased work stress and COVID-19 during the pandemic. Health systems need to do more to support these workers. Further research could investigate specific policy and procedural changes to benefit this under-recognized group in the greater healthcare workforce.

Failure of sterilization in a dental outpatient facility: Investigation, risk assessment, and management.

In 2017, an incident of failed sterilization of dental instruments occurred at a large dental outpatient facility in Singapore. We aim to describe findings of the investigation of the sterilization breach incident, factors related to risk of viral transmission to the potentially affected patients, and the contact tracing process, patient management, and blood test results at a 6-month follow-up. A full assessment of the incident was immediately carried out. The factors related to risk of viral transmission due to affected instruments were analyzed using 3 keys points: breached step(s) and scale of the incident, prevalence of underlying bloodborne diseases and immunity in the Singapore population, health status of potential source patients, and type of dental procedure performed, and health status of affected patients and type of dental procedure received. Up to 72 affected instrument sets were used in 714 potentially affected patients who underwent noninvasive dental procedures. The investigation revealed that there was a lapse in the final step of steam sterilization, resulting in the use of incompletely sterilized items. The assessment determined that there was an extremely low risk of bloodborne virus transmission of diseases to the patients. At the 6-month follow-up, there were no infected/colonized cases found related to the incident. Lapses in the sterilization process for medical and dental instruments can happen, but a risk assessment approach is useful to manage similar incidents. Quick response and proper documentation of the sterilization process can prevent similar incidents.

The effect of comorbidity on hospital mortality in patients with SLE from an Asian tertiary hospital.

OBJECTIVES: The objective of the study was to assess the disease burden of systemic lupus erythematosus (SLE) and the usefulness of the Charlson Comorbidity Index (CCI) as risk-adjusted hospital mortality predictors in patients with SLE using a hospital administrative database. METHODS: A historical cohort study of a hospital discharge database from 2004 to 2011 was used to identify cases with SLE and comorbidity using the International Statistical Classification of Diseases and Related Health Problems, ninth revision, Australian modification (ICD-9-AM) codes. RESULTS: Over the eight years, 841 patients met the criteria of SLE with a hospital mortality rate of 9.2%. The hospital mortality rates (2.4%, 15.7%, 25.0%, and 30.4%, respectively, p < 0.001) and hospital length of stay (geometric mean, 3.5, 5.6, 8.8, and 7.5 days, respectively, p < 0.001) were consistently increased for patients with CCI ranging from none, low, moderate to high grade, respectively. Cox proportional hazards model analysis showed that CCI (hazard ratio (HR) 7.8 high vs. none, p < 0.001) and infectious disease (HR 2.0, p = 0.016) were significant and independent predictors of hospital mortality. Similar results were also seen with hospital length of stay by zero-truncated negative binomial regression model analysis. CONCLUSION: The SLE burden is high in this population. Comorbidities and infectious disease were some of the most important contributors to hospital mortality and resource utilization.

HLA-DQ A1, -DQB1 and -DRB1 gene polymorphism--in Malay type 1 diabetes mellitus patients and their use for risk prediction.

HLA-DQA1, -DQB1, and -DRB1 gene polymorphism were analyzed to study type 1 DM susceptibility in Malay patients from Southeast Asia (Malaysia and Singapore). Patients showed significant increases in the occurrence of DQA1*0501 (50.7% vs. 20.4%; RR = 3.97; Pc < 0.01), DQB1*0201 (48% vs. 19.1%; RR = 3.86; Pc < 0.05), and DRB1*0301 (38.7 vs. 6.8%; RR = 8.36; 95% Pc < 0.05). Conversely, significant decreases were noted in the occurrence of DQA1*0601 (14.7% vs. 35.2%; RR = 0.33; Pc = 0.008) and DQB1*0601 (4% vs. 23.5%; RR = 0.16; Pc < 0.05) in type 1 DM patients. Using a logistic regression model, we derived a risk prediction model for type 1 DM in our indigenous Malay population based on the identified HLA genotypes. The RR for type 1 DM increases by a factor of 5.68 for every unit increase in the number of DRB1*0301 allele (P < 0.001), and decreases by a factor of 0.18 per unit increase in the number of DQB1*0601 allele (P < 0.001). After adjusting for these two HLA genotypes, DQA1*0501, DQB1*0201 and DQA1*0601 were not statistically significant as risk predictors. The lower incidence of type 1 DM in the Malay population may be contributed by the genotypic combinations of DR and DQ genes as well as the linkage disequilibria between susceptible and protective alleles.

Neuropsychiatric lupus: clinical challenges, brain-reactive autoantibodies and treatment strategies.

Neurological manifestations in lupus can be due to active lupus disease affecting the brain or to other reasons. Reversible posterior leucoencephalopathy syndrome, primary lymphoma of the central nervous system, cerebral infections by bacteria (e.g. mycobacteria), viruses (e.g. JC virus), fungi (e.g. Cryptococcus) and parasites (e.g. Acanthamoeba), steroid-induced psychosis and reactive depression need to be excluded. Brain-reactive autoantibodies have been described as associating with neuropsychiatric lupus. The strongest associations described to date are with antiribosomal P protein and antiphospholipid antibodies. However these autoantibodies have not been shown to play significant roles in the pathogenesis. Treatment strategy for severe neuropsychiatric lupus include establishing definitive diagnosis, early identification and treatment of aggravating factors, appropriate symptomatic treatment, adequate immunosuppression, selective B-cell depletion and autologous haematopoietic stem cell transplant. Systematic reviews have shown that cyclophosphamide administration is superior to pulse methylprednisolone as a maintenance therapy. Mycophenolate mofetil has been shown to have modest effect and should only be considered if cyclophosphamide cannot be administered.

Health-related quality of life of patients with systemic lupus erythematosus in Asia: how can this be improved?

The multicultural and multilinguistic landscape in Asia poses interesting challenges in the assessment and improvement of Health-Related Quality of Life (HRQoL) in Asian patients with systemic lupus erythematosus (SLE). This article highlights some of these challenges and addresses the issue of how to improve HRQoL of these patients by: (1) framing important concepts in HRQoL in relation to the chronic relapsing nature and multisystem involvement in this condition; (2) discussing ways to improve measurement of HRQoL of SLE patients in Asia by reviewing existing HRQoL instruments (both generic (i.e. the SF-36) and disease-specific (i.e. the L-QoL, LupusQoL, SLEQoL and SLE Symptom Checklist)) and item banking; and (3) discussing approaches to improving HRQoL in SLE.

Computerized administration of health-related quality of life instruments compared to interviewer administration may reduce sample size requirements in clinical research: a pilot randomized controlled trial among rheumatology patients.

OBJECTIVES: Computerized health-related quality of life (HRQoL) administration may facilitate clinical trials incorporating HRQoL assessment in rheumatology patients by reducing sample size requirements. We tested this hypothesis in a pilot randomized controlled trial. METHODS: Chinese-speaking adult rheumatology outpatients were randomized to computerized (PC) or interviewer (IA) administration of the EQ-5D (utility & VAS), Health Utilities Index (HUI2 & HUI3) and Family Functioning Measure (FFM). We compared measurement variability (i.e., variance) between PC and IA for each instrument before (Levene's test) and after adjusting for the effects of age, gender and education (multivariable modeling) and computed the variance ratio (VR) for PC over IA. RESULTS: In 138 patients (mean age: 48), the mean (SD) time for administration was similar for PC (n = 67) and IA (n = 71) at 17.7 (7.94) versus 17.3 minutes (7.49), respectively. More subjects expressed a preference for PC (n = 21) over IA (n = 13). Mean HRQoL scores were not significantly different for PC versus IA except for higher VAS scores with IA (difference -7.7, 95% CI -14.0 to 1.3, p = 0.018). Variances and adjusted VR were smaller with PC for the EQ-5D (adjusted VR 0.34, 95% CI 0.18 to 0.65), HUI3 (0.49, 0.27 to 0.89) and FFM (0.95, 0.61 to 1.46), but larger for the HUI2 (1.30, 0.67 to 2.55) and VAS (1.05, 0.55 to 2.00). CONCLUSION: The reduced variability in 3 of 5 instruments and good acceptance of computerized HRQoL assessment, if confirmed in larger studies, may lead to smaller sample size requirements, with potential reductions in cost and recruitment time for clinical trials and cohort studies.

Cross-cultural adaptation and validation of Singapore English and Chinese Versions of the Oxford Knee Score (OKS) in knee osteoarthritis patients undergoing total knee replacement.

OBJECTIVE: To cross-culturally adapt and validate Singapore English and Chinese versions of the Oxford Knee Score (OKS) in patients with knee osteoarthritis (OA) undergoing total knee replacement (TKR) surgery. METHODS: Singapore English and Chinese OKS versions were cross-culturally adapted from the source English version following standard guidelines (including cognitive debriefing), and validated by interviewing patients in English or Chinese using an identical, pretested questionnaire containing the OKS, Short Form 36, and EQ-5D. Reliability was assessed using Cronbach's alpha, dimensionality using principal component factor analysis and item-total correlations, convergent and divergent construct validity by assessing six and three a priori hypotheses, respectively. RESULTS: The Singapore English and Chinese OKS were well accepted by patients in pilot testing. When administered to a consecutive sample of 127 English and 131 Chinese-speaking Singaporeans with knee OA (mean age 66 years, 83% female, mean duration of OA 6 years, Chinese:Malay:Indian:Others=78:7.9:11:3.1% for English version), Cronbach's alpha exceeded 0.8 and factor analysis yielded three factors for both versions. Hypothesized item-total correlations (Spearman's rho > or = 0.4) were observed for all items except limping, kneeling, and night knee pain in both versions. Convergent construct validity was supported by the presence of hypothesized moderate/strong correlations (rho=0.37-0.73) for six and five a priori hypotheses in English and Chinese versions, respectively. Divergent construct validity was supported by the presence of weak correlations (rho=0.09-0.30) for all three a priori hypotheses in both versions. CONCLUSION: Singapore English and Chinese OKS demonstrated good patient acceptability and psychometric properties (including construct validity) among multiethnic Asian patients with knee OA undergoing TKR.

Cogan's syndrome with recurrent carotid and aortic aneurysms: a potentially fatal disorder mimicking Marfan syndrome.

Cogan's syndrome (CS) is a rare multisystemic disease characterized by vestibuloauditory dysfunction, inflammatory eye disease and vasculitis. Aortic aneurysms due to aortitis are under-recognized in CS, and are potentially fatal, with two of eight reported cases dying from aneurysm/arterial rupture. The presence of aneurysms was not recognized antemortem in both cases, highlighting the importance of early detection to prevent this potentially fatal outcome. We report a 17-year-old Chinese male with recurrent carotid and aortic aneurysms, bilateral sensorineural hearing loss, and recurrent scleritis who was initially thought to have Marfan syndrome. The diagnosis of CS was made 4.5 years after initial presentation, during which time recurrent aneurysms due to active aortitis (with aneurysmal rupture on one occasion) necessitated four surgical procedures. Treatment with methotrexate and corticosteroids resulted in no recurrence of aneurysms over 2 years of follow-up. This case illustrates (i) the challenges in diagnosing CS when various manifestations occur separately over a relatively long time period, (ii) that detection of aortic aneurysms in young patients, especially if recurrent, should prompt investigations for vasculitis/aortitis to prevent potentially fatal aneurysm rupture, and (iii) that methotrexate and high-dose corticosteroids may be effective in preventing development of further aneurysms in CS patients.

Visual disturbances in dengue fever: an answer at last?

Visual disturbances in dengue infection are uncommon but may result in permanent visual impairment. We report a 32-year-old Chinese woman with dengue infection and she developed retinal haemorrhage, retinal vasculitis and macular detachment. Autoimmune screen revealed a low C4 complement level, possibly due to partial C4 complement deficiency. The patient was treated with steroids and there was significant improvement in her vision. Partial C4 deficiency predisposes to autoimmune disease, and patients with pre-existing low C4 levels may be susceptible to ocular complications in dengue infection. Interestingly, previous case reports of ophthalmic complications of dengue infection occurred in young female patients, who are likewise predisposed to autoimmune disease. In conclusion, in individuals predisposed to autoimmune disease (females and patients with partial C4 deficiency), dengue infection may provide the antigenic trigger for immune complex deposition and retinal vasculitis. Steroids may have an important role in the treatment of this condition.

HLA-DRB1*04 gene polymorphisms and expressions profiles of interleukin-18 and interleukin-18 binding protein following in vitro stimulation in human peripheral blood mononuclear cells of healthy individuals and patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic arthritic condition that can lead to deformities and disabilities. Interleukin-18 (IL-18) is a proinflammatory cytokine known to play a role in the acute and chronic inflammatory phases of RA. IL-18 binding protein is the natural antagonist of IL-18 protein. We aim to identify the effect of HLA-DRB1*04 gene polymorphisms on IL-18 and IL-18BP gene expressions profiles as well as the time-course profiles following in vitro stimulation with mitogens. Peripheral blood mononuclear cells from 16 RA patients and 21 healthy controls were cultured for 1, 4, 8, 12, 24, 48 and 72 h following stimulation with either LPS or PHA. mRNA expression of IL-18 and IL 18BP were determined by quantitative real-time PCR using a comparative Ct (threshold cycle) method. IL-18 levels in supernatants were measured by enzyme-linked immunosorbent assay. Basal mRNA (4.5-fold) and protein levels of IL-18 were increased and IL-18BP mRNA expression was decreased (8-fold) in RA patients when compared to controls. Similarly, increased IL-18 levels were observed in active RA patients, whereas IL-18BP expression was increased in inactive patients. There was an increase in mRNA and protein levels of IL-18 in RA patients that peaked at 4 h and 8 h respectively following LPS stimulation. A similar profile was observed for IL-18BP; however, the expression level was higher in controls than RA patients. Persistent high production of IL-18 in RA is associated with disease progression and IL-18 BP seems to inhibit this activity.

Cross-cultural adaptation and validation of Singapore English and Chinese versions of the Lequesne Algofunctional Index of knee in Asians with knee osteoarthritis in Singapore.

OBJECTIVE: To cross-culturally adapt and validate Singapore English and Chinese versions of the Lequesne Algofunctional Index of knee in patients with knee osteoarthritis (OA) in Singapore. METHODS: Singapore English and Chinese versions were cross-culturally adapted from the source English version following standard guideline (including cognitive debriefing). Patients were asked to complete an identical, pretested questionnaire containing the Lequesne index, Short Form 36 Health Survey (SF-36), and EQ-5D twice within 6 days. Reliability was assessed using Cronbach's alpha and intraclass correlation coefficients (ICC). Dimensionality was assessed by principal component factor analysis. Construct validity was tested by item-to-scale correlations and 12 and six a priori hypotheses for convergent and divergent construct validities, respectively. RESULTS: Singapore English and Chinese Lequesne indices were well accepted by patients in pilot testing and were therefore administered to a consecutive sample of 127 English- and 131 Chinese-speaking Singaporeans with knee OA. Acceptable internal consistency was observed for activities of daily living and the global index (alpha=0.72-0.82), and the good test-retest reliability for all scales in both versions (ICC=0.66-0.94). Expected item-to-scale correlations were presented only in activities of daily living in both versions. Factor analysis yielded two factors for both versions. Convergent and divergent construct validities were supported by the presence of hypothesized correlations between the Lequesne index and SF-36 and EQ-5D scales. CONCLUSION: Both versions of the Lequesne index demonstrated acceptable reliability and validity among multiethnic Asian patients with knee OA, which suggests that it could be used as a global index in the health-related quality of life (HRQoL) measurements in Singapore and possibly other Asian countries.

Cross-cultural adaptation and validation of Singapore English and Chinese versions of the Knee injury and Osteoarthritis Outcome Score (KOOS) in Asians with knee osteoarthritis in Singapore.

OBJECTIVE: To cross-culturally adapt and validate Singapore English and Chinese versions of the Knee injury and Osteoarthritis Outcome Score (KOOS) in patients with knee osteoarthritis (OA) in Singapore. METHODS: Singapore English and Chinese versions were cross-culturally adapted from the source English KOOS following standard guidelines (including cognitive debriefing). Patients were asked to complete identical questionnaires containing the KOOS, Short Form 36 Health Survey, and EQ-5D twice within 6 days. Reliability was assessed using Cronbach's alpha and intraclass correlation coefficients (ICC), dimensionality using item-to-domain correlations and convergent and divergent construct validity using 14 and 13 a priori hypotheses, respectively. RESULTS: Singapore English and Chinese KOOS versions were well accepted by patients in pilot testing and were therefore administered to a consecutive sample of 127 English and 131 Chinese-speaking Singaporeans with knee OA. Cronbach's alpha exceeded 0.7 for all domains except for Chinese pain and symptoms domains. ICC exceeded 0.7 for all domains except for English sport and recreation and Chinese knee-related QoL domains. Hypothesized item-to-domain correlations (Spearman's rho>or=0.4) were observed for 38 items in English and 29 in Chinese versions. Convergent construct validity was supported by the presence of hypothesized moderate/strong correlations (rho=0.37-0.65) for 13 and 11 a priori hypotheses in the English and Chinese KOOS, respectively. Divergent construct validity was supported by the presence of weak correlations (rho=0.02-0.34) for 12 and 11 a priori hypotheses in the English and Chinese KOOS, respectively. CONCLUSION: The Singapore English and Chinese KOOS were well accepted and demonstrated acceptable reliability and validity in Asian patients with knee OA in Singapore.

Are they relevant? A critical evaluation of the international classification of functioning, disability, and health core sets for osteoarthritis from the perspective of patients with knee osteoarthritis in Singapore.

OBJECTIVES: To determine the extent to which health items identified from the perspective of patients with knee osteoarthritis can be linked with the International Classification of Functioning, Disability and Health (ICF); and to evaluate critically the content validity of ICF comprehensive and brief core sets for osteoarthritis. METHODS: Items identified from a focus group study were linked independently by two researchers based on the 10 a priori linking rules. Both percentage agreement and kappa statistics were calculated to measure interobserver agreement. Any disagreements were resolved by reaching a consensus among the researchers. The categories linked with all items were compared with the comprehensive core set, while the categories linked with those items reported as important by over 30% of subjects within each of three local ethnic groups (Chinese, Malay, and Indian) were compared with the brief core set. Both comparisons were made only at the second level of the ICF. RESULTS: In all, 74 items were linked with 44 different ICF categories through 105 linkages with generally good interobserver agreement. The 69 items were linked with the ICF at the third or fourth levels. Both commonalities and disparities were found through comparison between the categories linked with these items and both core sets. CONCLUSIONS: All items could be successfully linked with the ICF. The comprehensive core set showed good content validity, while the brief core set needs to be supported by more empirical evidence in various sociocultural contexts. This study specifically complemented the development and refinement of both core sets from the perspective of patients with knee osteoarthritis.

What health domains and items are important to patients with knee osteoarthritis? A focus group study in a multiethnic urban Asian population.

OBJECTIVES: To determine important health-related quality of life (HRQoL) domains and items within each domain affected by knee osteoarthritis (OA), identify ethnic variations in the importance of these domains and items among three ethnic groups, and determine how identified domains and items mapped onto selected OA-specific HRQoL instruments. METHODS: Focus groups were conducted among subjects with knee OA stratified by gender, ethnicity, and language spoken. All focus groups were audio-taped and transcribed verbatim, with subsequent translation into English for groups conducted in other languages. Data analysis was performed by combining the key elements of grounded theory and content analysis with the assistance of the qualitative software ATLAS/ti 5.0. RESULTS: Five domains (pain, physical disability, other symptoms of OA, mental health, and social health) were identified from the 74 items reported as important by at least one subject. These domains were important for subjects from all ethnic groups with the exception of social health, which was more often important for Malay subjects. Items more commonly reported as important in the pain, physical disability, and other symptoms of OA domains were generally similar across ethnic groups. In contrast, important items in the mental and social health domains differed among ethnic groups. CONCLUSIONS: The impact of knee OA on HRQoL is broadly similar in both Asian and Western socio-cultural contexts. Both similarities and differences in important domains and items were identified among subjects with knee OA from three major Asian ethnic groups.

Novel brain reactive autoantibodies: prevalence in systemic lupus erythematosus and association with psychoses and seizures.

Autoantibodies can cause neuropsychiatric manifestations in lupus patients by altering the physiological function of neuronal cells. In this study, we identified Brain Reactive Autoantibodies (BRAAs) against murine neuronal membrane proteins (M.W. 27.5 and 29.5 kD) and found them correlating with psychosis and/or seizures in lupus patients. They were specific to neuronal membrane tissues of mammalian origin and are significantly associated with psychosis and/or seizures (p<0.0001). These membrane proteins mass spectrometry profiles did not match to any published protein sequences. These BRAAs may play important roles in the pathophysiology of neuropsychiatric lupus.

PCR-RFLP genotyping for exon 1 and promoter region mutations of the human mannose binding lectin (MBL-2) gene.

The Mannose Binding Lectin (MBL) plays an important role in innate immunity and its genetic deficiencies are associated with frequent and prolonged infections. Serum MBL determination may not accurately detect acute phase protein levels and it is also difficult to detect dysfunctional protein. Genotyping of the exon 1 and promoter regions in the MBL gene will provide useful information on the presence of deficiencies in patients. A reproducible PCR-RFLP method is described to accurately detect genotypes of exon 1 and polymorphic haplotypes of the promoter region in the MBL gene.

Discriminative ability of the short-form 36 health survey: a tale of two versions.

BACKGROUND AND OBJECTIVES: Previous studies suggested that the Chinese version of the Short-Form 36 Health Survey (SF-36) had smaller variability in the physical functioning (PF) and physical component summary (PCS) scores than the English SF-36. This may translate into differences in discriminative ability and sample size requirement. MATERIALS AND METHODS: Data were drawn from a community-based survey and a randomised crossover study of Singaporeans bilingual in the Chinese and English languages. The abilities of the two PF and PCS versions in discriminating subjects who reported chronic illness and acute disease symptoms versus those who did not were compared. RESULTS: In all four comparisons (i.e. two health criteria in two studies) the Chinese version of PF showed a larger effect size than the English version. In three out of four comparisons the Chinese version of PCS showed a larger effect size than the English version. CONCLUSIONS: The Chinese version appeared more efficient in detecting a statistically significant difference between groups. Other factors being the same, the Chinese SF-36 may require a smaller sample size than the English SF-36 for the studies of physical aspects of health-related quality of life.

Modelling variability of quality of life scores: a study of questionnaire version and bilingualism.

BACKGROUND AND OBJECTIVES: Modelling variability of quality of life scores can not only improve our understanding of the characteristics of the measurement tools, but also shed light on sample size requirements. Although the English and Chinese versions of the Short Form 36 Health Survey (SF-36) are commonly considered equivalent, they have not been compared in terms of variability. Furthermore, bilingual and monolingual persons may differ in cognition and responses to questionnaires. METHODS: In a community-based survey of quality of life in Singapore, a society where both English and Chinese are widely used and bilingualism is prevalent, 2590 respondents answered either version of the SF-36. We studied the impact of questionnaire version and bilingualism on the variability of SF-36 scores by regression modelling, with adjustment for covariates. RESULTS: The Chinese version had smaller variances in the physical functioning (PF) and the physical component summary scores than the English version. The variance ratios (VRs) were respectively 0.32 and 0.60 (each p < 0.01), controlling for covariates. Bilingualism was not associated with variability in SF-36 scores except PF (VR = 0.78; p < 0.05). CONCLUSIONS: As a result of a smaller variance, using the Chinese version of SF-36 among bilingual Chinese people may require a smaller sample size than using the English version.