Place and Time Method of the Research Population and Sample

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CHAPTER III RESEARCH METHODOLOGY

This research investigates the pattern of past physical activity and the association of future osteoporosis fractures if osteoporosis risks are reduced with lifestyle changes. Providing evidence of an association between past physical activity and osteoporosis fractures supports public health policy and health improvement in which assist the population with affirmative actions that can prevent or reduce the likelihood of developing osteoporosis fractures.

A. Place and Time

The study is conducted in outpatient and orthopedic department of Malaysian Hospitals, Kuala Lumpur, Malaysia. University Malaya Medical Center and University Kebangsaan Malaysia Medical Center are selected as the study location. already diagnosed as osteoporotic patients visited outpatient department or admitted to orthopedic department between December 1 st 2013 until May 1 st 2014 are taken as subjects.

B. Method of the Research

Osteoporosis is diagnosed using a BMD test, a safe and painless way to detect low bone density. DXA scans are used to measure total body composition and fat content with a high degree of accuracy comparable to hydrostatic perpustakaan.uns.ac.id commit to user 54 weighing as a diagnostic measure. It estimates three body sections consisting of lean body mass, fat mass, and bone mass. These systems use a source that draws on two X-ray beams with differing energy levels, which are aimed at the patients bones. The differential attenuation of the two energies is used to estimate the bone mineral content. BMD can be determined from the absorption of each beam by bone. Body mass index refers to fat mass and lean body mass.

C. Population and Sample

All osteoporotic women of age between 50-80 who were already diagnosed as osteoporotic patients visited outpatient department or admitted to orthopedic department between December 1 st 2013 until May 1 st 2014 are taken as subjects. Sample Size Worldwide, approximately 30 of postmenopausal women have osteoporosis as defined by the WHO criteria and the prevalence of osteoporosis steadily increases with age. Sample size is calculated using the following formula Kish, 1965. n = Z 1- α 2 P1-PD 2 Z 1- α = Z 0.95 = 1.96 for CI of 95, Z = 1.96; normal ditribition table P = 0.01 = 0.0001 D = precision 0.3 30 perpustakaan.uns.ac.id commit to user 55 N = 1.96 2 0.051-0.050.3 2 = 72 Sample size of the study is 60 subjects. This figure is obtained as the minimum sample size of 40 by additional 10 20 subjects to compensate for non-response. Sample size = 60 subjects minimum of 40 subjects should be taken for this study.

D. Data Collection