|Year : 2010 | Volume
| Issue : 3 | Page : 385
Factors Associated with Attrition and Success in a Worksite Wellness Telephonic Health Coaching Program
RM Merrill1, DE Bowden2, SG Aldana3
1 Brigham Young University, Provo, Utah, USA
2 University of Wisconsin – Stevens Point, Stevens Point, Wisconsin, USA
3 WellSteps, Mapleton, Utah, USA
|Date of Submission||11-Aug-2009|
|Date of Acceptance||11-Sep-2010|
|Date of Web Publication||30-Nov-2010|
R M Merrill
229-A Richards Building, Provo, UT 84602
Source of Support: None, Conflict of Interest: None
Objectives: This study identifies factors associated with attrition and improvements in body mass index (BMI) in a telephonic health coaching program.
Methods: A cohort study design was used with 6,129 employees aged 21-88 years, enrolled in telephonic health coaching
sometime during 2002 through 2008.
Results: Attrition through 3, 6 and 12 months of follow-up was 13%, 17% and 36%, respectively. Those currently making
changes in physical activity or nutrition had the highest BMI (kg/m2), lowest levels of exercise and the poorest overall health at baseline. They were also most likely to continue with health coaching through 12 months. Those not ready to make changes at this time or having maintained an appropriate level of physical activity or nutrition for more than six months were least likely to continue with health coaching through 12 months. They also had the lowest BMI, highest levels of exercise and the best overall health. Among those continuing with health coaching through 12 months, the percent decrease in BMI between baseline and 12 months was: 1.5% for normal weight, 2.7% for overweight, 4.1% for class I & II obesity and 7.2% for class III obesity; 4.3% for high confidence to lose weight, 3.5% for medium confidence to lose weight and 3.1% for low confidence to lose weight; and 3.8% for very good or good general health, 4.5% for average general health and 6.8% for poor/very poor general health.
Conclusions: Attrition in the telephonic health coaching program is greatest among those least in need of behavior change. Of those who continued in the program, the greatest decrease in BMI occurred in those in greatest need for behavior change.
Behavior change, BMI, interactive health coaching, readiness to change, self-efficacy, weight
|How to cite this article:|
Merrill R M, Bowden D E, Aldana S G. Factors Associated with Attrition and Success in a Worksite Wellness Telephonic Health Coaching Program. Educ Health 2010;23:385
The need for behavior change in diet, physical activity, tobacco smoking and stress is evident from cross-sectional national surveys1. Lowering excessive body weight, high cholesterol and high blood pressure has become a primary objective of worksite health promotion programs. The worksite has been identified as an influential setting where health education can take place and health behaviors can improve2,3. There are many types of worksite wellness programs, including lifestyle coaching. Studies have demonstrated the effectiveness of lifestyle coaching at promoting positive behavior change, improving clinical outcomes and providing a positive return on investment4-8. A specific type of lifestyle coaching is administered using the telephone and the Internet. This approach has the advantage of increasing access to the healthcare coach and health education information.
The effectiveness of telephonic health coaching to encourage and motivate behavior change, boost confidence to make change (self-efficacy) and provide guidance and assistance in setting and reaching goals is a relatively new field of health promotion. Yet, some studies have shown this approach to be effective at positively influencing behavior change and clinical outcomes: Van Wier and colleagues used telephonic and electronic mail health coaching in the work setting to effectively lower body weight among overweight employees9; Vale and colleagues used telephonic health coaching and mailings to significantly reduce total cholesterol and other coronary risk factors among patients with coronary heart disease10; Tucker and colleagues found that 11 30-minute telephone-coaching sessions over 17 weeks sufficiently educated and motivated change in behaviors leading to weight loss11; and Hibbard and colleagues showed that telephonic health coaching tailored to the patients’ capabilities for self-management significantly increased activation scores, improved clinical indicators and decreased healthcare utilization rates12. Finally, Pomerantz and colleagues found that telephonic coaching to promote self-efficacy and optimal patient care decreased acute care facility admissions and length of stay in the care facility, reduced emergency department visits and produced a positive return on investment13.
With current trends in health risks and costs in the United States and elsewhere, telephonic health coaching is increasingly being seen as a potentially cost-effective approach to lower sick leave, improve productivity and minimize escalating healthcare costs among employees. In response, business service companies are now providing worksite wellness programs to various businesses, including telephonic health coaching. In the current study, we will consider a telephonic health coaching program that involves a baseline call, follow-up calls at 3, 6 and 12 months and additional access to the health coach for any needed support by telephone or online discussion. The details of this program are described below.
The purpose of this study is twofold. First, we will identify personal factors associated with attrition in the telephonic health coaching program. Second, among those who choose to remain in the coaching program through 12 months of follow-up, the study will evaluate the effectiveness of the program at reducing body mass index (BMI) according to physical activity and nutrition readiness to change variables and other selected factors.
Data: Ceridian is a business services company. One of its programs involves telephonic health coaching. Sixty-two organizations contracted with Ceridian sometime during 2001-2008 to provide telephonic health coaching to their employees through 12 months of follow-up. These companies covered the cost of this service to their employees. An initial intake and enrollment call and at least one follow-up call occurred among 6,195 individuals. Eight women were excluded from the study because of pregnancy. An additional 58 individuals were excluded because of missing information on stages of change with respect to nutritional and physical health behaviors. Analyses are based on 6,129 participants (Figure 1). The Scientific Advisory Board at Ceridian, which includes both internal and external advisors, and the Brigham Young University Institutional Review Board provided approval in March 2008 for an independent study of the telephonic health coaching program.
Figure 1: Flow diagram of study participation
Recruitment and Promotion: Recruitment into the telephonic health coaching program occurs throughout the program sponsorship period and through a variety of venues:
- A launch and communication package is provided to program sponsors/clients to communicate the initial roll-out of the program to participants.
- An ongoing print and electronic health promotion communication plan is created for each sponsor. This includes the use of promotions through a web portal, email messages, brochures, posters, wallet cards, newsletter articles, postcards, and announcement memos.
- Some sponsors choose to offer additional products and services which provide an opportunity to promote and recruit the health coaching programs. These include administration of a health risk assessment, health fairs, health screenings, and health and wellness seminars.
- During the coaching sessions, the coach shares additional services that may be of value to the participant.
- In addition to a self-referral model, there is an option for entry into the program through a manager-referral model. Managers who identify health, absence or presenteeism patterns may encourage employees to participate in the program to determine and help resolve root causes. Because individuals who could benefit most from the services may be the least likely to call with a self-referral model, incentives are also included for some sponsors/clients as part of their health coaching strategy.
- Another approach for entry into the program involves outreach and engagement, where individuals identified as at-risk for health and productivity issues are targeted. The process begins with the identification of the at-risk population. Following carefully established guidelines, outreach calls are made to those individuals identified to offer program supports and engage them in taking action for behavior change. This approach ensures that the individuals who would most benefit from the program are offered program resources.
Intervention: The telephonic health coaching program considered in this study was created by an interdisciplinary team of health professionals (registered dietitians, nutritionists, exercise physiologists and behavior health specialists) with the understanding that weight management often requires a life-long commitment. The program is based on a “one-day-at-a-time” philosophy, which includes planning the journey and breaking the change process into “one-behavior-at-a-time.”
The program focuses on healthy eating, with an emphasis on: reducing total calories, particularly saturated and trans fat; increasing vegetables, fruits and whole grains; and adding moderately intense physical activity most every day. With the assistance of the health coach, participants are taught to identify emotional eating triggers and how to change eating patterns and read food labels. They are instructed to drink adequate amounts of water, to keep track of food and beverage intake, to eat five or six small meals and snacks a day, to learn to control portion sizes, to add more fruits and vegetables to their diet, to increase consumption of whole-grains, to choose healthy snacks and desserts, to choose healthy beverages and to lower the amount of fat in their diet. Dietary guidelines are presented, based on the latest nutrition recommendations for healthy eating. This gives participants a more effective and practical guideline for creating their own healthy eating plan, incorporating foods they enjoy and ensuring maintenance of the program for the long term. Participants are also encouraged to adopt moderate-intense physical activity most days of the week and to make moderate and realistic weight loss goals. Finally, the importance of building and maintaining a support system for healthy lifestyle is emphasized.
The enrollment call is the first contact between the participant and the coach. During this call the coach attempts to: establish a positive, supportive and productive relationship with the participant; explain the health coaching concept and responsibilities of each partner; evaluate the participant’s medical history and current health behaviors; evaluate the participant’s readiness to change physical and nutritional behaviors; assess and enhance self-efficacy in the ability to make physical and nutritional behavior changes; provide the participant with information about smoking cessation or weight loss medications, where appropriate, and explain proper usage; help establish a plan of action and timeline; discuss strategies for change, relapse prevention and management of triggers; answer questions and concerns; provide physician or other healthcare professional referrals, when necessary; and provide access to additional resources. Participants interact with the same health coach throughout their enrollment in the program and have unlimited access to contact their health coach for any needed support via toll-free telephone calls or online discussions managed through the Health Coaching Website.
Follow-up calls at 3, 6 and 12 months after initial enrollment allowed the health coach to evaluate the adoption of lifestyle change(s) over a longer term. They also provided for: re-evaluation of the participant’s readiness to make and maintain changes; discussion of relapse prevention and management of triggers; re-evaluation of the results of lifestyle changes on health status as compared to triage; re-evaluation of symptoms of depression and anxiety; offers of support and encouragement; and plans for the next call.
The Health Coach: The health coaching program is overseen by an interdisciplinary team of health professionals (i.e., registered dietitians, nutritionists, exercise physiologists, behavioral health specialists, and a Doctor of Osteopathic Medicine). Coaches are required to have a degree in nursing, health education, exercise physiology, nutrition or public health, and to have clinical and behavior change expertise, pass a written and practical competency test, and have at least six months of mentored program training. Over 50% of the coaches have earned a graduate degree and the average professional experience of the coaches is 12 years.
Training of the health coaches is carried out through teleconferences and coaches are provided with a training manual. Training covers four focus areas. The first area covers theories of behavior change (i.e., the Health Belief Model and the Trans-theoretical Model of Change) and the practical application of theoretical constructs with participants14-16. The second area covers Miller's motivational interviewing, which focuses on developing a non-directive approach, reflective listening, empathy and managing ambivalence17. The third area focuses on clinical knowledge related to chronic and co-morbid conditions and their impact on behavior change. Depressive conditions and medications associated with weight loss are also considered. Depression screening is conducted, based on the work from the U.S. Preventive Services Task Force18. The fourth area focuses on database training: coaches are educated on how to collect data, conduct screenings and carry out proper documentation within the proprietary database.
Training the health coaches involves the use of case studies and role-plays as interactive tools to assess each health coach’s progress. Bi-monthly coach meetings are held to improve the "connection" between coaches. A different coach presents at each meeting, and the moderator position rotates through the coaches. The meetings involve training and team-building, and time is also allocated to discuss high-risk or unusual cases. Health coaches listen to a monthly podcast which discusses how new concepts and skills may be applied to their coaching.
The quality of the health coaching calls is monitored by a clinical consultant on a monthly basis. Operations staff members perform quality reports assessing satisfaction comments from participants, individual coach success rates per program and individual coach follow-up rates. The Quality Management Committee is a cross-functional team that meets monthly to review the coaching program and assess areas of quality improvement and program effectiveness. The Quality Management Committee reports its activities twice annually to the business unit Senior Management Team and submits its official work plan for yearly approval.
Outcome and Predictor Variables: Two outcome variables were evaluated in this study—whether the employee continued with telephonic health coaching through 12 months of follow-up and BMI. Body mass index was calculated as weight in kilograms divided by height in meters squared. Predictor variables included in the study were: age (21-39, 40-49, 50-59, 60 years and older); gender; baseline measures of current tobacco smoking status (yes, no); confidence to lose weight (yes, no); current use of weight loss medication (yes, no); days per week exercised at least 30 minutes on average; and general health status (very good, good, average, poor, very poor). Race was not considered in the study because 99% of participants were Caucasian.
Statistical Methods: Descriptive assessment of selected variables was made using frequencies, percentages, means and standard deviations. Logistic regression was used for characterizing attrition status and those who lowered their BMI at 3, 6 and 12 month assessments, adjusting for selected variables. Analysis of variance was used to compare BMI and days exercised per week according to physical and nutritional readiness to change variables. The F-statistic was also used for evaluating significant differences in means among independent groups, while adjusting for other variables. The chi-square statistic was used for evaluating bivariate relationships. Repeated measures analysis of variance was used to assess time trends in BMI according to age, gender and selected variables measured at baseline. Trends were evaluated using Wilks’ lambda. Statistical significance and confidence intervals were based on the 0.05 level. Analyses were performed using SAS version 9.2 (SAS Institute Inc., Cary, NC, USA, 2007).
There were 2,555 (42%) men and 3,574 (58%) women who received an initial coaching assessment. The average age of participants was 50.7 (sd = 10.1) years: 51.6 (sd = 10.2) for men and 50.1 (sd = 10.0) for women. The number of participants not available for follow-up coaching was 816 (13%) at 3 months, 1,022 (17%) at 6 months and 2,177 (36%) at 12 months. Forty-three percent of participants were sponsored by a large car manufacturing company, 32% by a large computer company, 9% by a large insurance company, 2% by a large research company, and the remaining 14% were sponsored by a number of smaller companies. After 12 months of follow-up, corresponding levels of participation in these groups were 47%, 32%, 9%, 3% and 9% (p < 0.001), respectively. Those in the car manufacturing company were more likely to continue with follow-up coaching through 12 months than those in the smaller companies. Attrition was significantly greater among participants who were: aged 21-39 years at baseline; women; less than very good health at baseline; on weight loss medication at baseline; and overweight or obese at baseline (Table 1).
Table 1: Status of Telephonic health Coaching Through 12 Months of Follow-up According to Selected Variables
Physical activity and nutrition readiness to change variables were significantly associated with age, gender, BMI, exercise and health status (Table2). Age was lowest for those not ready to make changes at this time. About 60% of individuals were currently making changes to physical activity or were planning to within the next six months. Men were more likely than women to have maintained an appropriate level of physical activity for more than six months. Sixty-three percent of women and 70% of men were currently making changes in nutrition or were planning to within the next six months. Women were more likely than men to have maintained an appropriate diet for more than six months. Higher BMI, lower levels of exercise and poorer health were associated with currently making changes or planning to make changes within the next six months.
Table 2: Physical Activity and Nutrition Readiness to Change According to Selected Variables
The level of readiness to change with respect to physical activity and nutrition was significantly associated with the likelihood of continuing with telephonic health coaching through 12 months of follow-up (Table 3). Individuals currently making changes in physical activity were significantly more likely to receive telephonic health coaching through 12 months, and those not ready to make changes in physical activity were least likely to be followed through 12 months. Participants currently making changes in nutrition or planning to were significantly more likely to receive telephonic health coaching through 12 months.
Table 3: Status of Telephonic health Coaching Through 12 Months of Follow-up According to Readiness to Change Variables
Among the 3,952 individuals who participated in telephonic health coaching through 12 months, BMI decreased for 57% of them through 3 months, 61% through 6 months and 62% through 12 months of follow-up. The percentage that lowered their BMI through 12 months was significantly associated with BMI at baseline: 50% for those with normal weight; 58% for those overweight; 66% for those with class I or II obesity; and 76% for those with class IV obesity (p < 0.001). Use of weight loss medication was not significantly associated with decrease in BMI after adjusting for baseline BMI.
A repeated measures design applied to those with complete follow-up information through 12 months showed a significant decreasing time trend for BMI. The decrease in trend significantly differed across the levels of stages of change for physical activity (p < 0.001) and for nutrition (p < 0.001), after adjusting for age and gender. Mean change in BMI (kg/m2) from baseline through 12 months was -1.3 for those currently making or planning to make changes in physical activity, -1.2 for those not ready to make changes in physical activity and -0.8 for those who had maintained an appropriate level of physical activity for more than six months (p < 0.001). Age and gender adjusted mean changes in BMI from baseline through 12 months was -1.3 for those currently making or planning to make changes in nutrition, -1.2 for those not ready to make changes in nutrition and -0.9 for those who had maintained an appropriate diet for more than six months (p = 0.015). When the BMI weight classifications at baseline were included in the repeated measures analysis, the physical activity stages of change variable became insignificant. This also occurred in the model containing the nutrition stages of change variable.
Further assessment of the repeated measures model involving BMI found that of those variables in Table 1, simultaneously significant variables were: baseline BMI weight classifications (p < 0.001); confidence to lose weight (p < 0.001); and general health status (p = 0.028). The percent decrease in BMI between baseline and 12 months was: 1.5% for normal weight, 2.7% for overweight, 4.1% for class I & II obesity and 7.2% for class III obesity; 4.3% for high confidence to lose weight, 3.5% for medium confidence to lose weight and 3.1% for low confidence to lose weight; and 3.8% for very good or good general health, 4.5% for average general health and 6.8% for poor or very poor general health.
This study identified factors associated with attrition in a telephonic health coaching program. The study then focused on employees who continued with telephonic health coaching through 12 months of follow-up. Among these individuals, the study evaluated the effectiveness of the health coaching program at reducing BMI according to readiness to change and other selected factors.
There appear to be two forces influencing attrition. First, those who are younger or female may feel there is less of a need to continue health coaching. This may be because the younger employees were significantly more physically active and more likely to have normal weight (data not shown). The higher level of female participation in this worksite health program is consistent with other health promotion programs19-21. The fact that women were more likely to discontinue participation may be, at least in part, because they had a significantly younger age distribution and were more likely to have a normal weight at baseline (data not shown). Second, some of those who were older with poorer health and higher BMI were simply less motivated to continue the coaching program. Some of this may be because their poorer health made it more difficult to continue with the program.
Continuing with telephonic health coaching through 12 months was greatest for those currently making changes in physical activity, followed by those planning to start making changes. These individuals had the greatest need to make changes given that they tended to have higher BMI, be less physically active and have poorer health status at baseline.
Those not ready to make changes in physical activity were least likely to continue with health coaching. These people had less of an incentive to change their behavior because they tended to have lower BMI, exercise more days per week and have better general health. A similar finding was observed for the nutrition readiness to change variable. Hence, the greatest attrition occurred among those in least need to make changes in weight, physical activity and overall health. This finding is consistent with the Health Belief Model in which a person may be aware of certain adverse health outcomes associated with selected risk behaviors, but unless these health outcomes are perceived to be personally threatening and serious, the potential benefits from behavior change may not outweigh the perceived costs of the behavior change22,23.
Among those who continued with telephonic health coaching through 12 months, decreasing trends in BMI over the study period were greatest for those currently making or ready to make changes, followed by those not ready to make changes and then those maintaining their current behavior for more than six months. However, adjusting for BMI weight classifications at baseline was sufficient to cause differences in decreasing trends in BMI across the stages of change for physical activity and nutrition to become insignificant.
In a revised repeated measures analysis, decreasing trend in BMI was independently influenced by baseline BMI, confidence to lose weight and health status. The decreasing trend was greatest for those who at baseline were obese, had low confidence to lose weight or were in poor/very poor health. Other studies have observed that the greatest decrease in health risks tends to occur in those who have higher health risks at baseline24-26.
The current telephonic health coaching program included the various components of the Health Belief Model. For example, according to their baseline health status, the program was clarified to each individual, identifying what he or she might gain from making tailored behavior changes or maintaining certain appropriate behaviors. Guidance in setting goals and the level of support extended by the health coach was also influenced by the participants’ readiness to change.
The observed benefits from telephonic health coaching are consistent with other studies9-13. Aspects of telephonic health coaching that may have contributed to the improvement in selected health behaviors include establishing baseline health history, status and behaviors. For some, behavior change is not needed, as indicated by the 13% who indicated that they had maintained appropriate levels of physical activity or nutrition for more than 6 months and were trying to stay on track. The telephonic health coaching program for them was tailored to assist these individuals to maintain their current lifestyle, consistent with the tailoring approach found to be effective elsewhere12. For those who were currently making or planning to make changes in physical or nutritional behavior, their actual weight, level of physical activity and confidence to lose weight indicated that these were the people with the greatest need for lifestyle coaching.
Assessing and boosting confidence in their ability to make and sustain behavior change (self-efficacy) was a primary part of the telephonic health coaching program. Higher confidence to lose weight had a significant, independent effect on lowering BMI. The important role of self-efficacy in behavior change illustrated here is consistent with the literature27. Furthermore, research has shown that individuals that have successfully made behavior change in the past tend to have greater confidence to do so in the future28. In the current study, overweight or obese individuals at baseline that improved their weight through 3 months were 190% more likely to have lower BMI through 6 months and 90% times more likely to have lower BMI through 12 months. In addition, perhaps greater confidence to lose weight among those in the maintenance stage is the result of greater success in losing weight in the past.
A limitation of this study is that participants self-selected into the program. Hence, they may not fully reflect the general employees. However, at baseline there was a broad distribution of BMI, physical activity and confidence to lose weight. Each of the readiness to change categories was also well represented. Loss to follow-up may limit generalization of the results to all employees. However, it may be appropriate to generalize the results to those employees with the greatest need for making behavior change, as reflected by those most likely to remain in the study. Individuals served as their own controls, and change over time in BMI and physical activity were of primary interest. In addition, while most participants reflected employees from the automobile, computer and insurance industries, we did not have specific information on the nature of their jobs (e.g., administration, maintenance, on an assembly line, or mostly standing or sitting). Further research may incorporate a separate comparison group to better control for potential confounding factors in evaluating the effectiveness of the telephonic health coaching program. Further research may also survey study participants for their perspectives on how and why they were successful or unsuccessful in making behavior change. Those elements of the lifestyle coaching intervention most likely to motivate behavior change can be further considered.
Those currently making changes in physical activity or nutrition had the highest BMI, lowest levels of exercise and the poorest overall health. They were also most likely to continue with health coaching through 12 months. On the other hand, those not ready to make changes at this time or having maintained an appropriate level of physical activity or nutrition for more than six months were least likely to continue with health coaching through 12 months. They also had the lowest BMI, highest levels of exercise and the best overall health. The greater attrition in those least in need of the program may be associated with the goals made with the health coach. The greatest decrease in BMI over the study period occurred in those most in need of behavior change, namely employees who were obese, had low confidence to lose weight and were in poor or very poor health at baseline.
1. Centers for Disease Control and Prevention. Behavior Risk Factor Surveillance System. Retrieved December 26, 2008, from: http://apps.nccd.cdc.gov/brfss
2. Katz DL, O'Connell M, Yeh MC, Nawaz H, Njike V, Anderson LM, Cory S, Dietz W. Public health strategies for preventing and controlling overweight and obesity in school and worksite settings: A report on recommendations of the Task Force on Community Preventive Services. MMWR Recommendations and Reports. 2005; 54(RR-10):1-12.
3. Chapman LS. Expert opinions on "best practices" in worksite health promotion (WHP). American Journal of Health-System Pharmacy. 2004; 18(6):1-6.
4. Bruno JL, Heimes S. Driving behavior change with interactive programs. Retrieved December 26, 2008, from: http://go.optumhealth.com/obmwp5
5. Fahey KF, Rao SM, Douglas MK, Thomas ML, Elliott JE, Miaskowski C. Nurse coaching to explore and modify patient attitudinal barriers interfering with effective cancer pain management. Oncology Nursing Forum. 2008; 35(2):233-240.
6. Merrill RM, Madanat H, Kelley AT, Layton JB. Nurse and physician counseling of patients about tobacco smoking in Jordan. Promotion & Education. 2008; 15(3):9-14.
7. Chapman LS, Lesch N, Baun MP. The role of health and wellness coaching in worksite health promotion. American Journal of Health-System Pharmacy. 2007; 21(6):1-10, iii.
8. Butterworth S, Linden A, McClay W, Leo MC. Effect of motivational interviewing-based lifestyle coaching on employees' physical and mental health status. Journal of Occupational Health Psychology. 2006; 11(4):358-365.
9. Van Wier MF, Ariens GA, Dekkers JC, Hendriksen IJ, Smid T, Van Mechelen W. Phone and e-mail counseling are effective for weight management in an overweight working population: A randomized controlled trial. BMC Public Health. 2009; 9(1):6.
10. Vale MJ, Jelinek MV, Best JD, Dart AM, Grigg LE, Hare DL, Ho BP, Newman RW, McNeil, JJ, COACH Study Group. Coaching patients on achieving cardiovascular health (COACH): A multicenter randomized trial in patients with coronary heart disease. Archives of Internal Medicine. 2003; 163(22):2775-2783.
11. Tucker LA, Cook AJ, Nokes NR, Adams TB. Telephone-based diet and exercise coaching and a weight-loss supplement result in weight and fat loss in 120 men and women. American Journal of Health-System Pharmacy. 2008; 23(2):121-129.
12. Hibbard JH, Greene J, Tusler M. Improving the outcomes of disease management by tailoring care to the patient's level of activation. The American Journal of Managed Care. 2009; 15(6):353-360.
13. Pomerantz JI, Toney SD, Hill ZJ. Care coaching: An alternative approach to managing comorbid depression. Professional Case Management. 2010; 15(3):137-142.
14. Prochaska JO, Norcross JC, DiClemente CC. Changing for good: The revolutionary program that explains the six stages of change and teaches you how to free yourself from bad habits. New York: W. Morrow; 1994.
15. Prochaska JO, Velicer WF. The transtheoretical model of health behavior change. American Journal of Health-System Pharmacy. 1997; 12(1):38-48.
16. Eisen M, Zellman GL, McAlister AL. A Health Belief Model-Social Learning Theory approach to adolescents' fertility control: Findings from a controlled field trial. Health Education Quarterly. 1992; 19(2):249-262.
17. Miller WR, Rollnick S. Motivational interviewing: preparing people for change. 2nd edn. New York: Guilford Press; 2002.
18. Screening for Depression. U.S. Preventive Services Task Force. Agency for Healthcare Research and Quality, Rockville, MD; 2002. Retrieved May 17, 2010, from: http://www.uspreventiveservicestaskforce.org/uspstf/uspsdepr.htm
19. Robroek SJ, van Lenthe FJ, van Empelen P, Burdorf A. Determinants of participation in worksite health promotion programmes: A systematic review. The International Journal of Behavioral Nutrition and Physical Activity. 2009; 6:26 (online).
20. Merrill RM, Aldana SG, Ellrodt G, Orsi R, Grelle-Laramee J. Efficacy of the Berkshire Health System Cardiovascular Health Risk Reduction Program. Journal of Occupational and Environmental Medicine. 2009; 51(9):1024-1031.
21. Aldana SG, Merrill RM, Price K, Hardy A, Hager R. Financial impact of a comprehensive multisite workplace health promotion program. Preventive Medicine. 2005;40(2):131-137.
22. Janz NK, Becker MH. The Health Belief Model: A decade later. Health Education Quarterly. 1984; 11:1-47.
23. Rosenstock IM. Historical origins of the Health Belief Model. Health Education Quarterly. 1974; 2:328-335.
24. Aldana SG, Greenlaw RL, Diehl HA, Salberg A, Merrill RM, Ohmine S, Thomas C. The behavioral and clinical effects of therapeutic lifestyle change on middle-aged adults. Preventing Chronic Disease. 2006; 3(1):A05.
25. Aldana SG, Greenlaw RL, Diehl HA, Salberg A, Merrill RM, Ohmine S, Thomas C. Effects of an intensive diet and physical activity modification program on the health risks of adults. Journal of the American Dietetic Association. 2005; 105(3):371-381.
26. Hyatt B, Merrill RM, Kumpfer K. Longitudinal outcomes of a comprehensive, incentivized worksite wellness program. Evaluation & the Health Professions. (In Press).
27. Strecher VJ, DeVellis BM, Becker MH, Rosenstock IM. The role of self-efficacy in achieving health behavior change. Health Education & Behavior. 1986; 13(1):73-92.
28. Marcus BH, Selby VC, Niaura RS, Rossi JS. Self-efficacy and the stages of exercise behavior change. Research Quarterly for Exercise and Sport. 1992; 63(1):60-66.