Chapter 4 Discussion
4.1 Discussion
Prior studies indicated osteoporosis prevention programs could significantly increase knowledge, health belief, self-efficacy, and calcium intake. Curry and colleagues (2002) provided a 30-minute osteoporosis educational program for community-based women. The results showed an increase in their knowledge about osteoporosis as well as their intent to use this knowledge. Sedlak and colleagues (2000) designed and implemented three osteoporosis educational programs with three levels of intensity – three 1-hour sessions, one 3-hour session, and one 45-minute session. Participants in all programs had significantly higher scores of knowledge after completing the programs. However, there was no change on health beliefs or behaviors to calcium intake and weight-bearing activities. A possible reason may be that the session time was too short to have an effect on health beliefs and behaviors (Rollnick, Mason & Butler, 1999). Knowledge can increase within a short amount of time, but perhaps not well maintain effect. However, health beliefs and behaviors seem to demand a longer amount of time to change. Our program consisted of an eight-week course (two hours per week), which was sufficient to change knowledge, health beliefs, and prevention behaviors.
Tussing & Chaoman-Novakofski (2005) provided educational intervention in women during eight weeks. Results of this project have increased health belief, self-efficacy, and behavior to calcium intake.
Nevertheless, the results of this project may be attributed to unknown external events because it had no control group. Piaseu and colleagues
(2001) provided a 3-hour osteoporosis educational program that was based on Social Cognitive Theory and Self-efficacy Model. The results showed increased knowledge, health belief, and self-efficacy. This program found that as a part of behavior change, self-efficacy was an important component of intervention programs for osteoporosis prevention. These results were similar to our program. However, our program also included an assessment of prevention behavior change (e.g.
calcium-rich foods intake, physical activities).
There are few studies on social support for participants in osteoporosis prevention programs. Most studies investigated social support regarding exercise interventions. These findings described exercise interventions to improve exercise behavior in older adults and recommended incorporation of social support (family, friend, and external support) to strengthen self-efficacy and outcome expectations related to exercise (Resnick, Orwig, Magaziner & Wynne, 2002). Women were more likely to adopt and to maintain physical activity recommended by family (Eaton, Reynes, Assaf, Feldman, Lasater & Carleton, 1993). We showed similar results in our program. Social support from friends, family, and medical staff could increase self-efficacy, calcium-rich food intake, and weight-bearing exercise through concern, encouragement, and praise.
Peterson and colleagues (2000) evaluated whether educational intervention would affect young women’s calcium intake and bone mass density (BMD) for three months. Results indicated that women in the treatment group made greater increases in total calcium intake and supplemental calcium than in the control group. Additionally, BMD in the
treatment group did not experienced significant changes while BMD in the control group showed significant losses. In another study, Winzenberg and colleagues (2006) performed a 2-year randomized controlled trial, which concluded that educational intervention could increase femoral neck BMD. Furthermore, femoral neck BMD increase was only significantly associated with starting calcium intake and sustaining physical activities. These results indicated that BMD needed to be assessed for a longer time period to determine the effect of intervention.
In our program, BMD significantly increased for three months.
In Study 1, the results indicated that the osteoporosis prevention program could effectively increase knowledge, health belief, self-efficacy, social support, and BMD. In addition, it could change behavior to calcium-rich foods intake and weight-bearing exercise on middle-aged and elderly women. Several studies demonstrated that knowledge and health belief of osteoporosis prevention could influence behavior of women. Women with high scores in knowledge and health belief demonstrate improved prevention behavior (Ali, 1996; Rubin &
Cummings, 1992; Yu & Huang, 2003). The most important factor to predict osteoporosis prevention behavior is self-efficacy, in particular, confidence in dietary calcium and weight-bearing exercise (Ali & Twibell, 1995; Piaseu, Belza & Mitchell, 2001; Stuifbergen & Becker, 1994).
Various studies in which participants improve and sustain physical activity or calcium intake show increased in bone mass. Particularly in women after menopause, effectiveness of exercise to increase BMD depended on adequate availability of dietary calcium (Borer, 2005;
Winzenberg, Oldenburg, Frendin, De Wit, Riley & Jones, 2006). Social
support is the major factor that assisted in physical activity (Nies, Vollman & Cook, 1998). Studies identified social support could affect change levels of exercise behavior (Resnick & Nigg, 2003; Sternfeld, Ainsworth & Quesenberry, 1999). When older adults obtain greater social support from friends, family and medical staff, they are more likely to engage in regular exercise.
In Study 2, the results indicated that the osteoporosis prevention program demonstrated positive effects on both rural and urban sites. In addition, participants in the rural site had higher social support than in the urban site. The finding may be attributed the older adults in the urban sites participate less in social activities and had little or no friendship networks than in the rural sites. Therefore, the urban older adults obtain less assistance from social support (Amato, 1993; Lin, 1995; Tseng, Lee
& Lee, 1995)
This osteoporosis prevention program used participative learning in teaching; for instance, a high-calcium recipe contest, model for weight- bearing exercise, panel discussion, and team games for calcium-rich foods. It focused on hands-on participation. The learning took place at the participant's center. These activities were not only interested to the participants, but also reinforced participants’ self-efficacy and social support, and sustained prevention behavioral changes.
Furthermore, National Osteoporosis Foundation, NOF, (2003) estimated that osteoporosis and low bone mass affected 44 million Americans who were above the age of 50, resulting in 1.5 million bone fractures per year in the United States and approximately 17 billion US dollars per year in medical treatment costs and lost productivity. In
Taiwan, femur fractures were estimated at thirty thousand per year and cost over 4 billion NT dollars in medical treatment (Department of Health Executive Yuan, 2003). In contrast to enormous medical treatment costs, our program only spent 1700 NT dollars per person, equal to approximately 50 US dollars per person. (Formula: compiled teaching materials cost + printed teaching materials cost + lecturer’s fees + presents cost + recipe contest cost + testing BMD cost / total participants).
Thus, it can be seen the osteoporosis prevention program is not only beneficial to participants, but it also is cost-effective.
4.2 Limitations
There were two limitations in this osteoporosis prevention program.
First, the participants were convenience samples; consequently, the results can not be used as true representation of the general public.
However, this limitation was common in past health promotion studies.
Because communities were different from hospitals, studies in the communities were difficult to randomly assign. Second, calcium-rich foods intake and weight-bearing exercise were self-reported. These estimations were not validated with objective measures. However, this program assessed participant’s calcium-rich foods intake and weight-bearing exercise behaviors per week to reduce bias.
4.3 Recommendations
Future studies could follow long-term effects of the osteoporosis prevention programs to determine whether prevention behaviors were sustained. In addition, one more control group from the urban sites could
be added to probe intervention effects between treatment group and control group. In the questionnaire, construct validity of perceived barriers only explained 29.01% variance, which was not perfect. Also, social support subscale had only emotional and informational factors to explain variance. Future studies could modify the questionnaire to obtain perfect construct validity of perceived barriers and to consider emotional, informational, instrumental, and appraisal factors into the social support subscale. In practice, this program may provide a basis for future osteoporosis prevention programs on middle-aged and elderly women, and may assist in developing practical health prevention programs that conform to the requirements of middle-aged and elderly women, and perhaps on middle-aged and elderly adults in general.
