Obesity: Worksite Programs
Summary of CPSTF Finding
Worksite nutrition and physical activity programs are designed to improve health-related behaviors and health outcomes. These programs can include one or more approaches to support behavioral change including informational and educational, behavioral and social, and policy and environmental strategies.
CPSTF Finding and Rationale Statement
Read the CPSTF finding.
About The Systematic Review
The CPSTF finding is based on evidence from a systematic review of 47 studies (search period 1966 – 2005). The review was conducted on behalf of the CPSTF by a team of specialists in systematic review methods, and in research, practice, and policy related to obesity prevention and control.
- Informational and educational strategies aim to increase knowledge about a healthy diet and physical activity. Examples include:
- Written materials (provided in print or online)
- Educational software
- Behavioral and social strategies target the thoughts (e.g. awareness, self-efficacy) and social factors that effect behavior changes. Examples include:
- Individual or group behavioral counseling
- Skill-building activities such as cue control
- Rewards or reinforcement
- Inclusion of co-workers or family members to build support systems
- Policy and environmental approaches aim to make healthy choices easier and target the entire workforce by changing physical or organizational structures. Examples of this include:
- Improving access to healthy foods (e.g. changing cafeteria options, vending machine content)
- Providing more opportunities to be physically active (e.g. providing on-site facilities for exercise)
- Policy strategies may also change rules and procedures for employees such as health insurance benefits or costs or money for health club membership.
- Worksite weight control strategies may occur separately or as part of a comprehensive worksite wellness program that addresses several health issues (e.g., smoking cessation, stress management, cholesterol reduction).
Summary of Results
Forty-seven studies qualified for the review and included three outcome measures: body mass index (BMI), weight, and percent body fat.
- The most common intervention strategies included both informational and behavioral skills components (32 studies). Few studies (4 studies) looked at policy and environmental changes in the worksite.
- Effects on the three outcomes consistently favored:
- The intervention group compared to the controls (31 studies)
- Those receiving more intensive versus less intensive strategies (9 studies).
- In individually randomized controlled trials, results showed that compared with control groups after 12 months, participating employees lost an average of 2.8 pounds (9 studies) and reduced their average BMI by 0.5 (6 studies).
- No one focus, diet or physical activity, or combination of both appeared to be better than others in terms of its effect on weight loss.
Summary of Economic Evidence
- The range of cost-effectiveness estimates from three studies varies from $1.44 to $4.16 per pound of loss in body weight (reported in 2005 dollars).
- One study conducted a cost-effectiveness analysis of a worksite weight-loss program consisting of three competitions held in business/industrial settings in which participants received a behavioral treatment manual at each weigh-in.
- Intervention costs for the three competitions were $6149, $1377, and $762, respectively, and included material costs and personnel time for management, employees, and program staff to organize and supervise the program.
- The cost per pound of weight lost in these three competitions was $4.16 for a 12-week program involving employees of three banks, $2.19 for a 13-week program, and $1.60 for a 15-week program respectively, with the last two competitions involving employees of two manufacturing companies. The lower cost per pound lost in Competitions 2 and 3 was due to decreased organizational expenses compared to Competition 1.
- One study analyzed the cost effectiveness of team competitions and estimated a cost of $1.45 to lose 1% of body weight.
- Costs included time of the committee that planned, coordinated, and administered the program, employee time, and minimal costs of photocopying manuals and material costs for posters.
- One study assessed the cost effectiveness of a 3-month worksite weight-loss program that included concepts of competition and self-responsibility in an education-based campaign.
- The campaign cost was $25,376 and the study reported a cost of $1.77 per pound of weight lost.
- One study reported costs for a self-help weight loss awareness campaign where each participant was given a kit with information on how to start a safe weight-loss program. Costs included personnel time and materials for typesetting, printing flyers, and posters.
- The intervention cost was $2634 excluding volunteer time and $3966 including 166 hours of volunteer time valued at $8.04 per hour.
- Cost-effectiveness ratios were $2.17 and $1.44, respectively, per pound of weight lost with or without the cost of volunteer time; however, the follow-up period was much shorter than that required for the effectiveness review.
- One study reported a reduction in disability and major medical costs of $1022.96 per participant at a worksite physical fitness program for a 1-year period, excluding costs of maternity or obstetrics-related claims.
- The intervention costs of $75,750 included the first-year budget for operating expenses, annual cost of laboratory tests and physical examinations, and annual cost of capital investment in equipment amortized more than 20 years.
- Although the study did not report any change in employee weight, there was a significant decline in the percentage of body fat.
- The intervention returned $1.59 for every dollar invested in the program resulting in a net saving of $0.59 per $1.00.
Based on the data available, the results of this review may be generalized to a white-collar workforce where both overweight and other chronic disease risk conditions exist.
CPSTF identified several areas that have limited information. Additional research and evaluation could help answer the following questions and fill remaining gaps in the evidence base. (What are evidence gaps?)
Although we found evidence that worksite programs targeting nutrition and physical behaviors confer modest, positive, weight-related benefits, important research questions remain. One of our initial review questions was only partially answered: which employee populations benefit the most from worksite health promotion interventions targeted at weight? Weight status varies considerably among employee populations. Reporting individual weight measure for employees from baseline to follow-up is not feasible in large occupational health studies. Instead, measurement of weight change in the studies we reviewed was usually presented as group mean change in BMI, pounds, kilograms, or percent body fat. Thus, we could not determine if those at greatest risk (i.e., overweight or obese) benefited more or less. Nor could we determine if a few employees lost a large amount of weight or if many employees lost small amounts. In addition to measuring mean weight change, it would also be useful to learn what percent of participants had clinically meaningful weight loss (i.e., >5% or >10 % body weight loss). Also, reporting changes in the prevalence of overweight and obesity in the employee population as a result of the intervention would provide information about intervention effects at the population-level. Highly effective interventions that reach only a small percent of the population will likely not affect the prevalence.
Forty percent the studies lacked information to determine differential effects according to blue or white collar job status. Those that did report occupational status included predominantly white collar workers. Race and ethnicity data were also limited.
A variety of worksite settings were represented in this review, which lends to the generalizability of the findings. Information on the feasibility of implementing programs across small to very large worksite settings, however, was hampered by missing workplace size data in 64% of the studies. We found no association between program effectiveness and focus of the program (e.g., CVD risk reduction, weight loss, physical fitness) or behavioral focus (diet or physical activity). Because the majority of programs used behavioral plus informational strategies, it was difficult to contrast program components with respect to effectiveness. Questions remain about the effect on employee weight status when implementation of environmental change (e.g., providing easy access to affordable, healthy foods, or modifying the physical environment to encourage physical activity) and employer policy strategies (health insurance incentives, contribution to gym membership fees, etc.) is included.
One third of the RCTs provided insufficient statistical information to allow meta-analytic pooling of effects. Only a few reported intention to treat analysis. Reporting on intervention intensity, duration, and fidelity was often ambiguous. Future studies will contribute more to the empirical knowledge base if they follow the CONSORT guidelines for reporting RCTs and TREND guidelines for reporting non-randomized studies.
- Half the studies were conducted in the U.S.; remaining studies were conducted in Europe, Australia, New Zealand, Japan, Canada, India, and Iceland.
- The purpose of the interventions, as stated by study authors, included CVD risk reduction (34%); weight control (26%); and physical fitness (19%).
- The behavioral focus of each intervention included diet and physical activity behaviors (57%); diet only (21%); and physical activity only (21%).
- Study participants were coded as white-collar or blue-collar workers based on descriptions in the studies and nature of the company. In 19 studies, this could not be determined; in 25 studies, the majority of participants (80%) held white-collar jobs; in the remaining four studies, the participants held blue-collar jobs.
- Among studies that reported gender of participants, most included both men and women (64%).
- Among 46 of the 47 included studies, the median sample size was 141 (range 29 3728). The final study, a WHO multicountry trial, had a sample size of 63,732.
- Of the 39 studies reporting attrition, the median attrition rate was 17% (range: 0% 82%).
Anderson LM, Quinn TA, Glanz K, et al. The effectiveness of worksite nutrition and physical activity interventions for controlling employee overweight and obesity: a systematic review. American Journal of Preventive Medicine. 2009;37(4):340-57.
Task Force on Community Services. A recommendation to improve employee weight status through worksite health promotion programs targeting nutrition, physical activity, or both. American Journal of Preventive Medicine. 2009;37(4):358-9.
Centers for Disease Control and Prevention. 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. 2005;54(RR-10):1-12. Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5410a1.htm.
Archer WR, Batan MC, Buchanan LR, et al. Promising practices for the prevention and control of obesity in the worksite. American Journal of Health Promotion. 2011;25(3):e12–26. Available at: http://www.ajhpcontents.com/doi/abs/10.4278/ajhp.080926-LIT-220.
Analytic Framework see Figure 1 on page 343
When starting an effectiveness review, the systematic review team develops an analytic framework. The analytic framework illustrates how the intervention approach is thought to affect public health. It guides the search for evidence and may be used to summarize the evidence collected. The analytic framework often includes intermediate outcomes, potential effect modifiers, potential harms, and potential additional benefits.
Summary Evidence Table
The number of studies and publications do not always correspond (e.g., a publication may include several studies or one study may be explained in several publications).
Primary Studies (47)
Abrams DB, Follick MJ. Behavioral weight-loss intervention at the worksite: feasibility and maintenance. Journal of Consulting & Clinical Psychology 1983;51(2):226-33.
Aldana SG, Greenlaw RL, Diehl HA, Salberg A, Merrill RM, Ohmine S. The effects of a worksite chronic disease prevention program. Journal of Occupational & Environmental Medicine 2005;47(6):558-64.
Anderson J, Dusenbury L. Worksite cholesterol and nutrition: an intervention project in Colorado. AAOHN J 1999;47(3):99-106.
Anderson JV, Mavis BE, Robison JI, Stoffelmayr BE. A work-site weight management program to reinforce behavior. J Occup Med 1993;35(8):800-4.
Baer JT. Improved plasma cholesterol levels in men after a nutrition education program at the worksite.[see comment]. J Am Diet Assoc 1993;93(6):658-63.
Barratt A, Reznik R, Irwig L et al. Work-site cholesterol screening and dietary intervention: the Staff Healthy Heart Project. Steering Committee. Am J Public Health 1994;84(5):779-82.
Briley ME, Montgomery DH, Blewett J. Worksite nutrition education can lower total cholesterol levels and promote weight loss among police department employees. J Am Diet Assoc 1992;92(11):1382-4.
Brownell KD SAMP. Weight reduction at the work site: a promise partially fulfilled. Am J Psychiatry 1985;142:47-52.
Bruno R, Arnold C, Jacobson L, Winick M, Wynder E. Randomized controlled trial of a nonpharmacologic cholesterol reduction program at the worksite. Prev Med 1983;12(4):523-32.
Cockcroft A, Gooch C, Ellinghouse C, Johnston M, Michie S. Evaluation of a programme of health measurements and advice among hospital staff. Occup Med (Lond) 1994;44(2):70-6.
Cook C, Simmons G, Swinburn B, Stewart J. Changing risk behaviours for non-communicable disease in New Zealand working men–is workplace intervention effective? New Zealand Medical Journal 2001;114(1130):175-8.
Crouch M, Sallis JF, Farquhar JW et al. Personal and mediated health counseling for sustained dietary reduction of hypercholesterolemia. Prev Med 1986;15:282-91.
DeLucia J, Kalodner C, Horan J. The effect of two nutritional software programs used as adjuncts to the behavioral treatment of obesity. J Subst Abuse 1989;1:203-8.
Drummond S, Kirk T. The effect of different types of dietary advice on body composition in a group of Scottish men. J Hum Nutr Diet 1998;11:473-85.
Elberson KL, Daniels KK, Miller PM. Structured and nonstructured exercise in a corporate wellness program: a comparison of physiological outcomes. Outcomes Manage Nurs Pract 2001;5(2):82-6.
Elliot DL, Goldberg L, Duncan TE et al. The PHLAME firefighters’ study: feasibility and findings.Am J Health Behav 2004;28(1):13-23.
Erfurt JC, Foote A, Heirich MA. Worksite wellness programs: incremental comparison of screening and referral alone, health education, follow-up counseling, and plant organization.Am J Health Promot 1991;5(6):438-48.
Forster JL, Jeffery RW, Sullivan S, Snell MK. A work-site weight control program using financial incentives collected through payroll deduction. J Occup Med 1985;27(11).
Fukahori M, Aono H, Saito I, Ikebe T, Ozawa H. Program of exercise training as Total Health Promotion Plan and its evaluation. Journal of Occupational Health 1999;41(2).
Furuki K, Honda S, Jahng D et al. The effects of a health promotion program on body mass index. J Occup Health 1999;41:19-26.
Gerdle B, Brulin C, Elert J, Eliasson P, Granlund B. Effect of a general fitness program on musculoskeletal symptoms, clinical status, physiological capacity, and perceived work environment among home care service personnel. J Occup Rehabil 1995; 5(1):1-16.
Gomel M, Oldenburg B, Simpson JM, Owen N. Work-site cardiovascular risk reduction: A randomized trial of health risk assessment, education, counseling, and incentives. Am J Public Health 1993;83(9).
Grandjean PW, Oden GL, Crouse SF, Brown JA, Green JS. Lipid and lipoprotein changes in women following 6 months of exercise training in a worksite fitness program. J Sports Med Phys Fitness 1996;36(1):54-9.
Harvey HL. An evaluation of RMH Health Club: Worksite wellness. Dissertation Abstracts International: Section B: The Sciences and Engineering 1998;60(2-B).
Hedberg GE, Wikstrom-Frisen L, Janlert U. Comparison between two programmes for reducing the levels of risk indicators of heart diseases among male professional drivers.Occup Environ Med 1998;55(8):554-61.
Jeffery RW, Forster JL, French SA et al. The Healthy Worker Project: a work-site intervention for weight control and smoking cessation. Am J Public Health 1993;83(3):395-401.
Juneau M, Rogers F, De Santos V et al. Effectiveness of self-monitored, home-based, moderate intensity exercise training in middle-aged men and women. Am J Cardiol 1987;60:66-77.
Karlehagen S, Ohlson CG. Primary prevention of cardiovascular disease by an occupational health service. Prev Med 2003;37(3):219-25.
Krishnan N, Varman M, Roberts M. Diabetes control: Role of health education and other factors. A study in a newspaper industry. Indian Journal of Industrial Medicine 2004;8(2).
Linenger JM, Chesson CV, Nice DS. Physical fitness gains following simple environmental change. Am J Prev Med 1991;7(5):298-310.
Lovibond SH, Birrell PC, Langeluddecke P. Changing coronary heart disease risk-factor status: the effects of three behavioral programs. J Behav Med 1986;9:415-37.
Muto T, Yamauchi K. Evaluation of a multicomponent workplace health promotion program conducted in Japan for improving employees’ cardiovascular disease risk factors. Prev Med 2001;33(6):571-7.
Nilsson PM, Klasson EB, Nyberg P. Life-style intervention at the worksite–reduction of cardiovascular risk factors in a randomized study. Scandinavian Journal of Work, Environment & Health 2001;27(1):57-62.
Nisbeth O, Klausen K, Andersen LB. Effectiveness of counselling over 1 year on changes in lifestyle and coronary heart disease risk factors. Patient Education & Counseling 2000;40(2):121-31.
Oden G, Crouse S, Reynolds C. Worker productivity, job satisfaction and work-related stress: the influence of an employee fitness program. Fitness Business 1989;4:198-204.
Okayama A, Chiba N, Ueshima H. Non-pharmacological intervention study of hypercholesterolemia among middle-aged people. Environmental Health & Preventive Medicine 2004;9(4).
Peterson G, Abrams DB, Elder JP, Beaudin PA. Professional versus self-help weight loss at the worksite: The challenge of making a public health impact. Behavior Therapy 1985;16(A2).
Pohjonen T, Ranta R. Effects of a worksite physical exercise intervention on physical fitness, perceived health status, and work ability among home care workers: five-year follow-up.Prev Med 2001;32(6):465-75.
Pritchard JE, Nowson CA, Billington T, Wark JD. Benefits of a year-long workplace weight loss program on cardiovascular risk factors. Nutr Diet 2002;59(2):87-96.
Proper KI, Hildebrandt VH, van der Beek AJ, Twisk JWR, Van MW. Effect of individual counseling on physical activity fitness and health: A randomized controlled trial in a workplace setting. American Journal of Preventive Medicine 2003;24(3).
Robison JI, Rogers MA, Carlson JJ et al. Effects of a 6-month incentive-based exercise program on adherence and work capacity. Medicine & Science in Sports & Exercise 1992;24(1).
Shimizu T, Horiguchi I, Kato T, Nagata S. Relationship between an interview-based health promotion program and cardiovascular risk factors at Japanese companies. Journal of Occupational Health 2004;46(3):205-12.
Talvi AI, Jarvisalo JO, Knuts L-R. A health promotion programme for oil refinery employees: Changes of health promotion needs observed at three years. Occupational Medicine (Oxford) 1999;49(2).
Thorsteinsson R, Johannesson A, Jonsson H, Thorhallsson T, Sigurdsson JA. Effects of dietary intervention on serum lipids in factory workers. Scand J Prim Health Care 1994;12(2):93-9.
Trent LK, Stevens L. Evaluation of the Navy’s obesity treatment program. Military Medicine 1995;160:326-30.
Wier LT, Jackson AS, Pinkerton MB. Evaluation of the NASA/JSC health related fitness program. Aviat Space Environ Med 1989;60:438-44.
World Health Organization European Collaborative Group. WHO European collaborative trial in the multifactorial prevention of coronary heart disease. 1989. Copenhagen, WHO.
Supplemental Papers (23)
Aldana SG, Greenlaw R, Diehl HA, Englert H, Jackson R. Impact of the coronary health improvement project (CHIP) on several employee populations. Journal of Occupational & Environmental Medicine 2002;44(9):831-9.
DeBacker G, Kornizter M, Dramaix M et al. Risk factor changes in the Belgian heart disease prevention project. Acta Cardiol Suppl 1979;23:377-84.
Erfurt JC, Foote A, Heirich MA. The cost-effectiveness of work-site wellness programs for hypertension control, weight loss, and smoking cessation. J Occup Med 1991;33(9):962-70.
Erfurt JC, Foote A, Heirich MA, Gregg W. Improving participation in worksite wellness programs: comparing health education classes, a menu approach, and follow-up counseling.American Journal of Health Promotion 1990;4:270-8.
Forster JL, Jeffery RW, Snell MK. One-year follow-up study to a worksite weight control program. Prev Med 1988;17(1):129-33.
Gregg W, Foote A, Erfurt JC, Heirich MA. Worksite follow-up and engagement strategies for initiating health risk behavior changes. Health Educ Q 1990;17(4):455-78.
Heirich MA, Foote A, Erfurt JC, Konopka B. Work-site physical fitness programs. Comparing the impact of different program designs on cardiovascular risks. J Occup Med 1993;35(5):510-7.
Kornitzer M, DeBacker G, Dramaix M et al. Belgian heart disease prevention project: incidence and mortality results. Lancet 1983;1:1066-70.
Kornitzer M, DeBacker G, Dramaix M, Thilly C. The Belgian heart disease prevention project. Modification of the coronary risk profile in an industrial population. Circulation 1980 January;61(1):18-25.
Menotti et al. Eight-Year Follow-up Results from the Rome Project of Coronary Heart Disease Prevention. Prev Med 1986;15:176-91.
Pritchard JE, Nowson CA, Wark JD. A worksite program for overweight middle-aged men achieves lesser weight loss with exercise than with dietary change.[see comment]. J Am Diet Assoc 1997;97(1):37-42.
Rose G, Heller RF, Pedoe HT, Christie DGS. Heart disease prevention project: a randomized controlled trial. Br Med J 1980;15:747-51.
Rose G, Tunstall-Pedoe HD, Heller RF. UK heart disease prevention project: incidence and mortality results. Lancet 1983;1:1062-5.
Schmitz K, French SA, Jeffery RW. Correlates of changes in leisure time physical activity over 2 years: The healthy worker project. Prev Med 1997;26(4).
Shephard RJ, Corey P, Cox M. Health hazard appraisal: the influence of an employee fitness program. Can J Pub Health 1982;73:183-7.
Shephard RJ, Corey P, Cox M. The impact of changes in fitness and lifestyle upon health care utilization. Can J Pub Health 1983;74:51-4.
Shephard RJ, Youldon PE, Cox M, West C. Effects of a 6-month industrial fitness programme on serum lipid concentrations. Atherosclerosis 1980;35:277-86.
Shephard RJ. Current perspectives on the economics of fitness and sport with particular reference to worksite programmes. Sports Medicine 1989;7(5).
Shephard RJ. Twelve years experience of a fitness program for the salaried employees of a Toronto life assurance company. Am J Health Promot 1992 March;6(4):292-301.
Shephard RJ. Worksite fitness and exercise programs: a review of methodology and health impact. Am J Health Promot 1996;10(6).
Wier LT, Jackson AS. Factors affecting compliance in the NASA/Johnson Space Center fitness programme. Sports Med 1989;8(1):9-14.
World Health Organization European Collaborative Group. Multifactorial trial in the prevention of coronary heart disease 2. Risk factor changes at two and four years. Eur Heart J 1982;3:184-90.
World Health Organization European Collaborative Group. Multifactorial trial in the prevention of coronary heart disease: 3. Incidence and mortality results. Eur Heart J 1983;4(3):141-7.
Bowne D, Russell M, Morgan J, Optenberg S, Clarke A. Reduced disability and health care costs in an industrial fitness program. J Occup Med 1984;26(11):809 16.
Brownell K, Cohen R, Stunkard A, Felix M, Cooley N. Weight loss competitions at the work site: impact on weight, morale and cost-effectiveness. Am J Pub Health 1984;74(11):1283 5.
Erfurt J, Foote A, Heirich M. The cost-effectiveness of worksite wellness programs for hypertension, control, weight loss, and smoking cessation. J Occup Med 1991;33(9):962 70.
Nelson D, Sennett L, Lefebvre RC, Loiselle L, McClements L, Carleton R. A campaign strategy for weight loss at worksites. Health Ed Res 1987:2(1):27 31.
Seidman L, Sevelius G, Ewald P. A cost-effective weight loss program at the worksite. J Occup Med 1984;26(10):725 30.
Stunkard A, Cohen R, Felix M. Weight loss competitions at the worksite: how they work and how well. Prev Med 1989;18:460 74.
The following databases were searched for studies between the date indicated and
December 2005: MEDLINE (1966); EMBASE (1980); Cumulative Index to Nursing and Allied Health Literature (CINAHL, 1982); PsycINFO (1967); SPORTDiscus (1966); Latin American and Caribbean Health Sciences Literature (1996), Dissertation Abstracts (1980), and the Cochrane Library (2005).
Following are the MeSH terms and text words used in the searches:
Workplace or worksite
Occupational health services or occupational health
Obesity or obese
Physical activity or motor activity
Body mass index
Risk reduction behavior
Hand searches of the American Journal of Preventive Medicine, Occupational Medicine, and the International Journal of Obesity were conducted for the years 2004 through 2005. The reference lists of prior literature reviews, as well as reference lists from studies included in this review, were used to identify relevant articles. Experts in obesity or worksite interventions were consulted for additional citations. Searches were limited to literature published in English.
The search strategy combined key economic terms such as cost, cost benefit, cost utility, and cost-effectiveness analyses with the terms used in the effectiveness review. In addition to the databases searched for th4he effectiveness review, this search also included economic-specific databases including Econ-Lit and the Social Science Citation Index.
Considerations for Implementation
The following considerations are drawn from studies included in the evidence review, the broader literature, and expert opinion.
- When more or more intensive modes of intervention were provided to participants there appeared to be an increase in program impact. For example, offering structured programs (i.e., scheduled sessions) appears more effective than unstructured approaches, and information plus behavioral counseling confers more benefit than providing information alone.
- There was no apparent difference in program effectiveness based on lay versus professional group leaders.
- Obesity prevention programs at worksites may enhance employee self-confidence and improve the relationship between management and labor, and boost profits by increasing employee productivity and reducing medical care and disability costs.
Evidence-Based Cancer Control Programs (EBCCP)
Healthy People 2030
Healthy People 2030 includes the following objectives related to this CPSTF recommendation.
- Reduce the proportion of adults with obesity — NWS‑03
- Increase the proportion of worksites that offer an employee physical activity program — ECBP-D04
- Increase the proportion of worksites that offer an employee nutrition program — ECBP-D05
Health Impact in 5 Years (HI-5)
HI-5 highlights community-wide approaches that have demonstrated 1) positive health impacts, 2) results within five years, and 3) cost effectiveness and/or cost savings over the lifetime of the population or earlier.