Efficacy of Three Modes of Weight Loss Intervention - Essay Example

A Research Plan A. Efficacy of Three Modes of Weight Loss Intervention Among Pre-Menopausal Women B. Using randomized controlled trials, the study will attempt to compare the efficacy of three modes of weight loss intervention among women in the pre-menopausal age range. The experiments will be designed to test the null hypothesis that there are no significant differences in the weight loss means among the three modes interventions administered. The main research instruments will include a self-report questionnaire, a block food frequency questionnaire, and actual measurements of significant health parameters such as weight, height, body mass index (BMI), waist circumference, total body fat, free fat mass, physical activity, and nutrient intake. Three equally-sized groups of 34 women each will be randomly assigned to three modes of weight loss intervention. The first group will receive only nutritional counselling from a certified nutritionist in a group setting scheduled on a once a week meeting for a period of six months. The second group will participate in a group weight and cardiovascular training program which meets thrice a week for one hour sessions within a six month period. The third group will receive both nutritional counselling and weight/cardiovascular training similar to the first and second groups, respectively. Descriptive and inferential statistics will be utilized to analyze the data gathered from the controlled trials, particularly the simple mean and one-way analysis of variance. Non-directional or two tailed analysis and a level of significance of 0.05 (α = 0.05) will be used in hypotheses testing. C. Statement of the research problem 1. Rationale and justification of the study Obesity as a global health problem is already widely recognized (World Health Organization, 2000; James, 2003; Haslam, Sattar and Lean, 2007; Lovejoy, 2009). It was, however, noted by Lovejoy (2009) that while the world sees the significance of obesity as a global epidemic, there seem to be less recognition that the prevalence of obesity is higher among women around the world and that obesity presents differential health risks in women. Based on the sex-specific clinical guidelines for obesity from the National Institutes of Health (in Lovejoy, 2009), a waist circumference of more than 88 centimeters (or approximately 35 inches) places a woman at an increased health risk. Cooper, Fairburn and Hawker (2003) identified the main health risks of obesity as hypertension (which is associated with risk of stroke), cardiovascular disease (such as coronary artery disease, peripheral vascular disease, and heart failure), abnormal cholesterol levels (associated with risk of heart disease), diabetes, sleep apnea, osteoarthritis, and gall bladder disease. Women who are overweight, however, face greater risks for postmenopausal breast cander, endometrial cancer and pre-menopausal ovarian cancer. Moreover, women who are obese face greater risks for polycystic ovarian syndrome (PCOS) and PCOS-related infertility (Lovejoy, 2009). At menopause, decreased estrogen is produced. As explained in Lovejoy (2009), decreased estrogen in menopausal women tend to result in changes in their body fat distribution, which in turn would most likely result to changes in the metabolism in adipose tissue. Hence, women in the pre-menopausal and menopausal stage tend to gain more weight. To counteract the risks associated with weight gain during the menopausal stage, there should be conscious efforts on the part of healthcare practitioners to emphasize that weight gain is among the modifiable risk factors which may be controlled through weight management, fat restriction, and increased physical activity. The primary justification, therefore, for the study is two-fold: first, findings of the study will present significant evidence that there are effective interventions against weight gain during the pre-menopausal stage, and that successful weight management from any one of the programs will add to the repository of recent studies which will encourage overweight women in the pre-menopausal stage that there are potent interventions against the dreaded weight gain during this stage for women. 2. Significance of the study Findings of the study will be significant to enhance the quality of life of pre-menopausal women, especially those who tend to gain more weight during this period. Additional knowledge on the efficacy of options for weight management will help health practitioners in recommending the best program which will generate more fruitful results for a particular menopausal case. The study will also be significant to the medical community on account of the other diseases in which obesity or being overweight is a risk factor. D. Statement of the purpose of the study 1. Specific aims or objectives The study will venture to compare the efficacy of three modes of intervention for weight management among women in the menopausal stage. Specifically, the study has the following objectives: a. Describe the profile of the study participants in terms of the following variables: age, weight, height, BMI, waist circumference, total body fat, free fat mass, physical activity, and nutrient intake (total calories, total fat, saturated fat and dietary cholesterol), b. Report the average weight loss (or gain) among the three groups based on their initial weight and their weight at the end of the six-month intervention period. c. Evaluate whether the mean of the weight loss (or gain) among the three groups of participants significantly differed. d. Determine which of the variables considered in the study may be significantly associated with weight loss during the pre-menopausal stage. 2. Research hypotheses or guiding questions The following hypotheses, stated in the null form will be tested using non-directional or two-tailed analysis and a 0.05 level of significance: a. There are no significant differences in the mean weight loss among the participants in the three modes of weight management intervention conducted. b. There are no significant associations between weight loss at the end of the six-month controlled trials and any of the profile variables considered in the study. E. Background of the study 1. Topics for the review of literature related to: a. Theory and supportive rationale b. Related studies c. Methods 2. Previous work by the investigator that supports the project This proposed study is the first of its kind to be investigated by this researcher. Hence, a discussion of any previous work regarding the project is not needed. F. Method 1. Subjects, characteristics, sampling methods and plans for recruitment A total of 102 respondents will participate in the study, which will be randomly assigned to three groups or 34 participants per group. The sample size was based on the proportion of women population in Boston, Massachussetts who are in their menopausal stage. Data for the sample size computation was taken from the US Bureau of Census (2008) and from Varney, Kriebs, and Gegor (2004) who maintained that the range of menopause is between the ages of 48 and 55. From the total population of women in Boston of 314,458, around 6.3 per cent of this number fall within the pre-menopausal age range of menopause or approximately 19,810. Using the web-based sample size calculator and the following parameters: (a) margin of error of 7%; (b) level of confidence of 95%; (c) population size of 33,000;and (d) response distribution of 15%, the minimum recommended sample size is 100. The output of the online calculation of sample size is shown in the appendix. From the computed sample size, three groups of 34 each will be recruited. The eligibility criteria for inclusion as respondents in the study are: (a) female; (b) age between 45-49; (c) menstruating regularly; (d) not taking any medications for thyroid; (e) not taking prescription or non-prescription weight loss medication; and (f) no physical limitations which will preclude the participant from doing the required exercise should she be grouped under the second or the third group. Respondents will be recruited from female patients of obstetric and gynecology practitioners in the private and public clinics around the Boston area who are willing to sign informed consent forms and are willing to participate for a six-month period. 2. Materials, instrumentation, plans to establish reliability and validity Instrumentation will include a self-report profile form indicating the respondent’s age, menopausal status and pre-menopausal symptoms and a Block food frequency questionnaire for the measurement of nutrient intake. The following medical equipment will also be used for the required measurements in the study: (a) beam balance scale for measuring weight; (b) stationary vertical height board for measuring height; (c) accurate tape measure for measuring waist circumference; (d) a dual energy X-ray absorptiometer (DXA) using the array mode for measuring total body fat and free fat mass; (e) Caltrac accelerometer for measuring physical activity; and (f) a calculator to facilitate calculations. There is almost no need to test reliability and validity of instruments since the Block food frequency questionnaire already has established validity while the self-report profile practically does not need to be validated since it is just a short and simple checklist which indicates pre-menopausal status through symptoms experienced by the respondent. It may also be validated, if needed for verification purposes, from the respondents’ OB records. 3. Procedures a. Study design The study will adopt randomized controlled trials in each design which, according to Stolberg, Norman and Trop (2004) is the most powerful type of experimental study. A randomized control trial, as defined in Stolberg, et al., “is a study in which people are allocated at random to receive one of several clinical interventions”. As explained by Stolberg, et al., the intervention usually refers to a treatment, but may be used in a wider sense to include “any clinical maneuver offered to study participants that may have an effect on their health status”. b. Details of test and treatment administration Three equally-sized groups of 34 women each will be randomly assigned to three modes of weight loss intervention. The first group will receive only nutritional counselling from a certified nutritionist in a group setting scheduled on a once a week basis for a period of six months. The second group will participate in a group weight and cardiovascular training program which meets thrice a week for one hour sessions within a six month period. The third group, on the other hand, will receive both nutritional counselling from a certified nutritionist in a group setting scheduled once a week for a period of six months, as well as a weight/cardiovascular training program which meets thrice a week for one hour within a period of six months. c. Data collection methods Data for the age, menopausal status and pre-menopausal symptoms will be gathered on the first day of the six-month period together with the administration of the Block food frequency questionnaire and the signing of the informed consent forms. The two questionnaires will not require the names of the participants, but will use respondent code numbers which will be use to gather data regarding each respondent for the duration of the study. All other data will be measured directly by a nurse who will provide assistance to the researcher regarding all weight, height and other measurements pertinent to the study. The nurse is blinded as to the group assignments of the study participants. Measurements, except for physical activity, will be taken at the start of the study, and at exactly one month intervals until the end of the six-month period. The respondents will be asked to answer the Block food frequency questionnaire each day for a period of six months so that daily total calories, total fat, saturated fat and dietary cholesterol can be assessed with the help of the certified nutritionist. For the physical activity, the Caltrac accelerometer will be pre-programmed to control for the differences in the basal metabolic rate. Each participant will wear the monitor for 2 consecutive weekdays and one weekend day during the second month of the program. Data from the three days will be averaged. d. Timetable Figure 1 presents the Gantt chart for the timetable of the proposed study Figure 1. Gantt chart of the research timetable Year 2010 1 2 3 4 5 6 7 8 9 Feb Mar Apr May Jun Jul Aug Sep Oct Proposal writing Approval from ethics committee Recruitment of participants Conduct of controlled trials Data analysis Writing of research report Dissemination of findings As shown in the Gantt Chart in Figure 1, the proposal was prepared during the third week of February. Upon submission of the research plan, three weeks waiting time was allotted for the approval of the study by the ethics committee. Upon approval by the ethics committee, a vigorous recruitment operation will be conducted in for two weeks. The randomized controlled trials is scheduled to run from April to September. Data analysis is scheduled to start by August and to end by the second week of October. Writing of the complete research report will commence at the end of the controlled trials. The last two weeks of October is allotted for the preparations which will culminate in the reporting of the research findings via an oral defense of the study or presentation in a research forum. 4. Data management and analysis Data will be recorded digitally in a data matrix using the MS Excel program and appropriately number coded to facilitate data analysis. Hypothesis testing using repeated measures analysis of variance will be carried out using the software Statistical Package for the Social Science (SPSS) Version 17. Profile of the study participants in terms of the different variables will be presented as pie charts. Average weight loss among the three groups will be shown using tabular data. Results of the evaluation of significant differences in the mean weight loss among the three groups, as well as significant associations between mean weight loss and the different variables considered in the study will be presented in tabulated form. G. Literature cited Cedars, M. I. & Evans, M. (2008). Menopause. In R. S. Gibbs, B. Y. Karlan, A. F. Haney & I. Nygaard (Eds.), Danforth’s obstetrics and gynecology. 10th ed. (pp. 725-741). Philadelphia, PA: Lippincott, Williams & Wilkins. Cooper, Z., Fairburn, C. G. & Hawker, D. M. (2003). Cognitive-behavioral treatment of obesity: a clinician’s guide. New York: The Guilford Press. Haslam, D. Sattar, N. & Lean, M. (2007). Obesity-time to wake up. In N. Sattar & M. Lean (Eds.), ABC of obesity (pp. 1-3). Malden, MA: Blackwell. James, P. (2003). Obesity: a global problem. In L. Voss & T. Wilkin (Eds.), Adult obesity: a paedriatric challenge (pp. 1-12). London: Taylor & Francis. Lovejoy, J. C. (2009). Pregnancy and menopause. In C. A. Nonas & G. D. Foster (Eds.), Managing obesity: a clinical guide. 2nd ed. (pp. 260-274). Chicago, IL: American Dietetic Association. Raosoft (2004). Sample size calculator. Retrieved February 19, 2010, from http://www.raosoft.com/samplesize.html?margin=9&confidence=95&population=33000&response=40&sample1=100&sample2=200&sample3=300&confidence1=90&confidence2=95&confidence3=99 Stolberg, H. O., Norman, G. & Trop, I. (2004). Randomized controlled trials. American Journal of Roentgenology, 183, pp. 1539-1544. Retrieved February 20, 2010, from http://www.ajronline.org/cgi/content/full/183/6/1539 US Bureau of Census (2008). Age and Sex: Boston City, Massachusetts. Retrieved February 19, 2010, from http://factfinder.census.gov/servlet/STTable?_bm=y&-geo_id=16000US2507000&-qr_name=ACS_2008_3YR_G00_S0101&-ds_name=ACS_2008_3YR_G00_&-redoLog=false Varney, H. Kriebs, J. M. & Gegor, C. L. (2004). Varney’s midwifery. 4th ed. Sudbury, MA: Jones & Bartlett. World Health Organization (2000). Obesity: preventing and managing the global epidemic. Geneva: World Health Organization H. Documentation of Informed Consent I. Appendix 1. Screenshot of the output from on an online sample size calculator (Raosoft, 2004). Read More