PURPOSE: In this study, a framework comprising equivalence and cognition models was used to assess and finalize the Heart Quality-of-Life (HeartQoL)-Bahasa Malaysia (BM) questionnaire, which was derived from both forward-backward (FB) and dual-panel (DP) translation methods.
METHODS: Investigation and finalization of two initial versions of the questionnaire were conducted based on findings from an expert assessment (n = 3 sociolinguists blinded to translation methods) and cognitive interviews with purposively sampled patients (FB: n = 11; DP: n = 11). The equivalence model of Herdman et al. and the question-and-answer model of Collins were adapted to form a "cognition-and-equivalence" model to guide data collection and analysis through modified cognitive interviews. The final HeartQoL-BM was completed by 373 patients with ischemic heart disease from two medical centers, and the data were analyzed using confirmatory factor analysis to assess the evidence of equivalence.
RESULTS: Findings from the expert assessment and cognitive interview showed the existence of semantic and item equivalence on almost all of the FB and DP items, identified some subtle potential equivalence gaps, and guided the process of item finalization. Confirmatory factor analysis, including tests of factorial invariance on the final two-factor model of HeartQoL-BM, confirmed conceptual, item, measurement, and operational equivalence, which supports functional equivalence.
CONCLUSIONS: The potential use of the cognition-and-equivalence model for modified cognitive interviewing and the application of the six equivalence types of Herdman et al. were supported by the HeartQoL-BM showing functional equivalence with its source. HeartQoL-BM is a potentially valid measure of health-related quality of life for patients with ischemic heart disease independent of conditions such as angina, myocardial infarction, and heart failure.
METHODS: Out of 105 patients with IHD, 76 completed self-administration of HeartQoL at the clinic followed by at home within a 2-week interval. In retest, patients responded using non-interview methods (phone messaging, email, fax, and post). Phone interviewing was reserved for non-respondents to reminder.
RESULTS: Reliability of HeartQoL was good (intraclass correlation coefficients = 0.78-0.82), was supported in the Bland-Altman plot, and was comparable to five studies on MacNew of similar retest interval (MacNew-English = 0.70-0.75; translated MacNew = 0.72-0.91). Applicability of its standard error of measurement (0.20-0.25) and smallest detectable change (0.55-0.70) will depend on availability of normative data in future.
CONCLUSION: The reliability of HeartQoL is comparable to its parent instrument, the MacNew. The HeartQoL is a potentially reliable core IHD-specific HRQoL instrument in measuring group change.
METHODS: This cross-sectional, retrospective cohort study was conducted at the University of Malaya Medical Centre from 1 May 2013 until 30 May 2013. We analyzed the lipid profiles (total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides) of 629 patients before and at least 3 months after switching them from proprietary atorvastatin (Lipitor®) to generic atorvastatin (atorvastatin calcium from Ranbaxy Laboratories, Inc.). We also investigated if there was any difference in the effectiveness of both atorvastatin formulations in various ethnic groups.
RESULTS: 266 patients were included in this study. When comparing the median values we found no statistically significant differences (Wilcoxon signed-rank test; p
METHOD: DPSC from murine incisors were isolated through either the outgrowth (DPSC-OG) or the enzymatic digestion (DPSC-ED) method. Cells at passage 4 were used in this study. The cells were characterized through morphology and expression of cell surface markers. The cells' doubling time when cultured using different seeding densities was calculated and analyzed using one-way ANOVA and Tukey's multiple comparison post-test. The ability of cells to differentiate to chondrocyte and osteoblast was evaluated through staining and analysis on the matrices secreted.
RESULTS: Gene expression analysis showed that DPSC-OG and DPSC-ED expressed dental pulp mesenchymal stem cell markers, but not hematopoietic stem cell markers. The least number of cells that could have been used to culture DPSC-OG and DPSC-ED with the shortest doubling time was 5 × 10(2) cells/cm(2) (11.49 ± 2.16 h) and 1 × 10(2) cells/cm(2) (10.55 h ± 0.50), respectively. Chondrocytes differentiated from DPSC-ED produced 2 times more proteoglycan and at a faster rate than DPSC-OG. FTIR revealed that DPSC-ED differentiated into osteoblast also secreted matrix, which more resembled a calvaria.
DISCUSSION: Isolation approaches might have influenced the cell populations obtained. This, in turn, resulted in cells with different proliferation and differentiation capability. While both DPSC-OG and DPSC-ED expressed mesenchymal stem cell markers, the percentage of cells carrying each marker might have differed between the two methods. Regardless, enzymatic digestion clearly yielded cells with better characteristics than outgrowth.