INTRODUCTION: The Third National Health and Morbidity Survey Malaysia 2006 includes a nutritional status assessment of children. This study aimed to assess the inter- and intra-examiner reliability, the technical error of measurement and the validity of instruments for measuring weight, height and waist circumference.
METHODS: A convenience sample of 130 adults working in a selected office setting was chosen to participate in the study, subject to the inclusion and exclusion study criteria. Two public health nurses, trained to follow a standard protocol, obtained the weight, height and waist circumference measurements. The weight was measured using the Tanita HD-318 digital weighing scale to the nearest 0.1 kg, and Seca Beam Scale to the nearest 0.01 kg. The height was measured using the Seca Bodymeter 206 and Stadiometer, both to the nearest 0.1 cm. The waist circumference was measured using the Seca circumference measuring tape S 201, to the nearest 0.1 cm.
RESULTS: The intra-examiner reliability in descending order was weight and height followed by waist circumference. The height measurement, on average, using the test instrument, reported a recording of 0.4 cm higher than the reference instrument, with the upper and lower limits at 2.5 cm and 1.6 cm, respectively. The technical error of measurement and coefficient of variation of weight and height for both inter-examiner and intra-examiner measurements were all within acceptable limits (below five percent).
CONCLUSION: The findings of this study suggest that weight, height and waist circumference measured in adults aged 18 years and above, using the respective above mentioned instruments, are reliable and valid for use in a community survey. Limiting the number of examiners, especially for waist circumference measurements, would yield a higher degree of reliability and validity.
The National Health and Morbidity Survey III 2006 wanted to perform anthropometric measurements (length and weight) for children in their survey. However there is limited literature on the reliability, technical error of measurement (TEM) and validity of these two measurements. This study assessed the above properties of length (LT) and weight (WT) measurements in 130 children age below two years, from the Hospital Universiti Kebangsaan Malaysia (HUKM) paediatric outpatient clinics, during the period of December 2005 to January 2006. Two trained nurses measured WT using Tanita digital infant scale model 1583, Japan (0.01kg) and Seca beam scale, Germany (0.01 kg) and LT using Seca measuring mat, Germany (0.1cm) and Sensormedics stadiometer model 2130 (0.1cm). Findings showed high inter and intra-examiner reliability using 'change in the mean' and 'intraclass correlation' (ICC) for WT and LT. However, LT was found to be less reliable using the 'Bland and Altman plot'. This was also true using Relative TEMs, where the TEM value of LT was slightly more than the acceptable limit. The test instruments were highly valid for WT using 'change in the mean' and 'ICC' but was less valid for LT measurement. In spite of this we concluded that, WT and LT measurements in children below two years old using the test instruments were reliable and valid for a community survey such as NHMS III within the limits of their error. We recommend that LT measurements be given special attention to improve its reliability and validity.
Study site: Paediatric clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
Obesity is an emerging public health threat in the elderly population in developing countries. Hence, the Third National Health and Morbidity Survey has assessed 4746 individuals aged 60 years and older recruited through a household survey to determine the prevalence of adiposity using body mass index and waist circumference. The national's prevalence of overweight and obesity in men was 29.2% (95% confidence interval [CI] = 27.2-31.3) and 7.4% (95% CI = 6.4-8.6), respectively. However, the prevalence decreased with age. The figures in women were 30.3% (95% CI = 28.5-32.1) and 13.8% (95% CI = 12.5-15.2), respectively. The prevalence of abdominal obesity was 21.4% (95%CI = 20.2-22.6), with 7.7% (95% CI = 6.7-9.0) in men and 33.4% (95% CI = 31.4-35.3) in women. Predictors of adiposity include the following: Malay and Indian ethnicity, higher education level, higher household income, from urban area, and being married. In conclusion, adiposity affects about one third of the Malaysian elderly population, especially those of the younger age group, women, and those with higher socioeconomic status.
Study name: National Health and Morbidity Survey (NHMS-2006)
Generalised obesity and central obesity are risk factors for Type II diabetes mellitus and cardiovascular diseases. Waist circumference (WC) has been suggested as a single screening tool for identification of overweight or obese subjects in lieu of the body mass index (BMI) for weight management in public health program. Currently, the recommended waist circumference cut-off points of > or = 94cm for men and > or =80cm for women (waist action level 1) and > or = 102cm for men and > or = 88cm for women (waist action level 2) used for identification of overweight and obesity are based on studies in Caucasian populations. The objective of this study was to assess the sensitivity and specificity of the recommended waist action levels, and to determine optimal WC cut-off points for identification of overweight or obesity with central fat distribution based on BMI for Malaysian adults. Data from 32,773 subjects (14,982 men and 17,791 women) aged 18 and above who participated in the Third National Health Morbidity Survey in 2006 were analysed. Sensitivity and specificity of WC at waist action level 1 were 48.3% and 97.5% for men; and 84.2% and 80.6% for women when compared to the cut-off points based on BMI > or = 25kg/m2. At waist action level 2, sensitivity and specificity were 52.4% and 98.0% for men, and 79.2% and 85.4% for women when compared with the cut-off points based on BMI (> or = 30 kg/m2). Receiver operating characteristic analyses showed that the appropriatescreening cut-off points for WC to identify subjects with overweight (> or = 25kg/m2) was 86.0cm (sensitivity=83.6%, specificity=82.5%) for men, and 79.1cm (sensitivity=85.0%, specificity=79.5%) for women. Waist circumference cut-off points to identify obese subjects (BMI > or = 30 kg/m2) was 93.2cm (sensitivity=86.5%, specificity=85.7%) for men and 85.2cm (sensitivity=77.9%, specificity=78.0%) for women. Our findings demonstrated that the current recommended waist circumference cut-off points have low sensitivity for identification of overweight and obesity in men. We suggest that these newly identified cut-off points be considered.
Study name: National Health and Morbidity Survey (NHMS-2006)
The Third National Health and Morbidity Survey (NHMS III) was conducted in 2006 on a nationally representative sample of population in Malaysia. Over 21,000 children aged 0-17.9 years were measured for body weight and stature according to the protocol of the World Health Organization. This article describes the nutritional status of children aged 0-59.9 months. Mean z score for weightfor-age (WAZ), height-for-age (HAZ) and BMI-for-age were compared with the z-scores tables of the WHO standards. The overall prevalence of underweight and stunting of the children were 12.9% and 17.2% respectively. These levels included 2.4% severe underweight and 6.0% severe stunting. In terms of z scores, the age group of 0-5.9 months showed the best nutritional status with mean WAZ of -0.33 (95%CI: -0.52, 0.15) and -0.40 (-0.57, 0.24) for boys and girls respectively, while mean HAZ was 0.64 (0.38, 0.89) for boys and 0.76 (0.54, 0.98) for girls. Mean HAZ and WAZ status was least satisfactory after about 6 months, suggesting a faltering in growth rate at an age that coincides with dependence on complementary feeding. Prevalence of overweight based on BMI-for-age for the sexes combined was 6.4%, while that based on WAZ was 3.4%. The NHMS III results indicate that Malaysian children have better nutritional status compared to children under 5 years in neighbouring countries. In order to meet the targets set in the National Plan of Nutrition (2006-2015), more effective intervention programmes are needed to accelerate the reduction of underweight and stunting, and to arrest the rise of overweight in young children.
Study name: National Health and Morbidity Survey (NHMS-2006)
This study sought to examine the reliability of two measurements; Calf Circumference (CC) and Mid-half Arm Span (MHAS). A sample of 130 elderly persons aged 60 years and above seen consecutively in the Kuala Lumpur Hospital outpatient clinic during the period of December 2005 to January 2006, upon consent, were recruited to the study. There was a high degree of reliability for both inter- and intra-examiner (r close to 1). For inter-examiner, on average the CC measurements taken by the first examiner were 0.3 cm lower than that of the second examiner. The upper and lower limit of the differences were +0.4 to -0.9 cm respectively. Inter-examiner MHAS measurements on average by the first examiner were 0.2 cm lower than that of the second examiner. The limits were +1.7 to -2.1 cm. By comparison, the inter-examiner CC measurements were more reliable than the MHAS measurements. For intra-examiner, on average the CC measurements at Time 1 were consistent with Time 2 (mean difference=0) with limits of the difference at + 0.5 cm. MHAS measurements at Time 1 were on average 0.1 cm less than at Time 2 with limits at +1.7 and -1.8 cm. The technical error of measurement (TEM) and coefficient of variation of CC and MHAS for both interexaminer and intra-examiner measurements were within acceptable limits with the exception of MHAS TEM. This study suggests that CC and MHAS measured in elderly persons 60 years and above, using Seca Circumference Tape ® 206, Germany (0.05 cm) are reliable and can be used in a community survey.
Study site: Outpatient clinic, Hospital Kuala Lumpur
Abdominal obesity (AO) is an independent risk factor for cardiovascular disease, hypertension and diabetes mellitus in adults. There is a lack of data on the magnitude and socio-demographic profile of AO among Malaysian adults at the national level. In the Third National Health and Morbidity Survey (NHMS III) conducted in 2006, AO of adults aged 18 years and above was determined based on the waist circumference as part of the nutritional status assessment. This article reports the prevalence of AO in relation to socio-economic factors and demographic characteristics of adult subjects. Out of a total of 33,465 eligible individuals 18 years and above, waist circumference was measured in 32,900 (98.3%) individuals. The prevalence of AO was assessed using the cut-off points recommended by World Health Organization. The mean waist circumference in men and women was 84.0cm [95% confidence interval (95% CI): 83.8, 84.3] and 80.3cm (95% CI: 80.1, 80.6) respectively. The national prevalence of AO was 17.4% (95% CI: 16.9, 17.9). The identified risks of AO were women (OR: 4.2, 95% CI: 3.8, 4.6), aged 50-59 years (OR: 5.6, 95% CI: 4.0, 7.7), Indians (OR: 3.0, 95% CI: 2.4, 3.8), housewives (OR: 1.4, 95% CI: 1.1, 1.7), subjects with primary education (OR: 1.3, 95% CI: 1.1, 1.5) and ever married (OR: 1.4, 95% CI: 1.2, 1.6). Being the largest population-based study on AO among Malaysians, these findings have important public health implications. There is an urgent need to revise public health policies and programmes aimed at prevention of abdominal obesity especially in the groups at risk.
Study name: National Health and Morbidity Survey (NHMS-2006)