The use of monetary incentives in a community survey: impact on response rates, data quality, and cost

OBJECTIVES: To assess the effect of incentive size on response rates, data quality, and cost in a digestive health status mail survey of a community sample of health plan enrollees. DATA SOURCES/SETTING: The study population was selected from a database of enrollees in various health plans obligated to receive care at Park Nicollet Clinic-HealthSystem Minnesota, a large, multispecialty group in Minneapolis, Minnesota, and the nearby suburbs. STUDY DESIGN: A total of 1,800 HealthSystem Minnesota enrollees were randomly assigned to receive a survey with an incentive of $5 or $2. The response rates for each incentive level were determined. Data quality, as indicated by item nonresponse and scale scores, was measured. Total cost and cost per completed survey were calculated. PRINCIPAL FINDINGS: The response rate among enrollees receiving $5 (74.3 percent) was significantly higher than among those receiving $2 (67.4 percent); differences were more pronounced in the first wave of data collection. Data quality did not differ between the two incentive groups. The total cost per completed survey was higher in the $5 condition than in the $2 condition. CONCLUSIONS: A $5 incentive resulted in a higher response rate among a community patient sample with one mailing than did a $2 incentive. However, the response rates in the $2 condition approached the level of the $5 incentive, and costs were significantly lower when the full follow-up protocol was completed. Response rates were marginally increased by follow-up phone calls. The incentive level did not influence data quality. The results suggest if a survey budget is limited and a timeline is not critical, a $2 incentive provides an affordable means of increasing participation.     

Effects of enhanced calling efforts on response rates,estimates of health behavior,and costs in a telephone health survey using random-digit dialing.

Public health researchers frequently rely on random-digit dialing (RDD) telephone surveys in monitoring trends in health behavior and evaluating health promotion interventions. RDD response rates have declined during the past decade, and cost-effective methods to increase response rates are needed. The authors evaluated two levels of enhanced calling efforts in an RDD survey of cancer-related health behavior in the State of Washington. The first level of enhanced calling effort was 1 month after 11 original calling attempts to a household, when the authors attempted up to 11 recalls. The second level was 6 months after the first answered call, when the authors recalled those persons who could not be interviewed. Enhanced calling efforts increased the overall survey response rate by 11 percent. Nine percentage points of the increase were attributable to call backs. There were demographic differences among the participants reached at different levels of calling effort, but no consistent associations of level of calling effort with health behavior related to alcohol use, smoking, diet, or health screening. Marginal costs for interviews completed with enhanced calling efforts were about 50 percent higher than costs for interviews reached in the first 11 calls. The authors concluded that enhanced calling efforts may be justified, because they increase confidence in the generalizability of survey results. However, the authors found very little change in survey results by including interviews from persons who were difficult to reach and to interview.     

Prepayment was superior to postpayment cash incentives in a randomized postal survey among physicians

OBJECTIVE: Improving response rates, particularly among physicians, is important to minimize nonresponder bias and increase the effective sample size in epidemiologic research. We conducted a randomized trial to examine the impact of prepayment vs. postpayment incentives on response rates. STUDY DESIGN AND SETTING: Self-completion postal questionnaires were mailed to 949 physicians who were respondents to an earlier survey and representative of the general physician population in Hong Kong. These physicians were randomly allocated to receive a HK dollar 20 cash prepayment incentive that accompanied the survey (n=474) or a postpayment reward of the same amount on receipt of the completed questionnaire (n=475). RESULTS: The final prepayment response rate was 82.9%, compared with 72.5% in the postpayment arm (P < .001). Of the eight alternative incentive and follow-up strategies evaluated, three lie on the efficiency frontier (i.e., not dominated), including postpayment with three mailings at HK dollar 42.7, prepayment with three mailings at HK dollar 66.5 and prepayment with three mailings and telephone follow-up at HK dollar 112.1 per responder recruited (US dollar 1=HK dollar 7.8). CONCLUSION: The findings demonstrate that prepayment cash incentives are superior to postpayment of the equivalent amount in improving response rates among a representative sample of Hong Kong physicians. Further research should concentrate on confirming the generalizability of these findings in other health care occupation groups and settings.     

Journals read by community physicians: results of a national survey

Summary A postal survey of community physicians employed by English health authorities revealed that area medical officers read more journals than any other group of respondents and that younger community physicians read more journals than older ones. TheBritish Medical Journal (95 per cent) is the most widely read journal followed byCommunity Medicine (90 per cent). Although epidemiology is considered by the great majority as important to work and for continuing education, relatively few read the specialist epidemiology journals.     

Effects of characteristics of the survey instrument on response rates to a mail survey of community hospitals.

A 4-factor, 16-cell experimental design was used to investigate the relationship between response rates of community hospitals to a survey conducted by the American Hospital Association (AHA) and 4 characteristics of the survey instrument, each varied dichotomously: the perceived length of the questionnaire, the order of questions, the orientation of the appeal made in the cover letter, and the presence or absence of a promise to share the results of the study with respondents. Response rate variations between the various cells were examined and multiple logistic regression was used to analyze the significance of the association between response rates and each of the four survey instrument variables while controlling for the effect of the others. At the same time, control was also maintained for the effects of five institutional characteristics of hospitals which a previous study had shown to have a significant relationship to response: bed size, location within or outside a standard metropolitan statistical area, AHA membership status, type of ownership, and form of control. The perceived length of the questionnaire and the order of questions were found to have a significant effect on response rates, but the orientation of the cover letter and a promise to share the results of the study with the respondents were found to be insignificant.     

Can physicians treat tuberculosis? Report on a national survey of physician practices.

OBJECTIVES: Researchers examined physicians' treatment strategies for tuberculosis to determine whether they would follow recommendations of the Centers for Disease Control and Prevention and the American Thoracic Society. METHODS: A national survey sampled 1772 physicians. Analyses tested correlates of recommended treatment regimens. RESULTS: Among respondents, 59.4% described a recommended regimen. Specialists; physicians aware of professional publications, treatment recommendations, and reporting requirements; and those having more than 50% of patients in nursing homes were more likely to describe recommended regimens. Physicians who had been in practice longer, relied on personal experience, or had more than 50% of patients receiving Medicaid were less likely to describe recommended regimens. CONCLUSIONS: Physicians who treat tuberculosis require training and support. Policymakers should consider who should treat tuberculosis and how recommended practice should be ensured.     

Ill-health retirement: national rates and updated guidance for occupational physicians

BACKGROUND: Advising on ill-health retirement is an important role of most practising occupational physicians. In recent years, the eligibility criteria and process for gaining early retirement benefits have changed in many pension schemes in the UK. AIM: To investigate the variation in rates of retirement due to ill-health in National Health Service (NHS) Trusts and Local Authorities and to update previously published guidance on ill-health retirement with specific reference to pension schemes with eligibility criteria that include permanence of incapacity due to ill-health. METHODS: Rates of retirement were calculated for 222 NHS Trusts and 132 Local Authorities with more than 1500 employees. Literature searches and consensus statements by the authors. RESULTS: Rates of retirement were widely distributed in the NHS Trusts and Local Authorities. The median rates of retirement were 2.11 (IQR 1.37-2.91)/1000 active members and 4.10 (IQR 3.01-6.10)/1000 employees, respectively (P<0.001). Difficulties in the doctor-patient relationship and in ascertaining the true functional ability of some patients were identified. CONCLUSION: There continues to be marked variation in rates of early retirement due to ill-health within and between organizations that warrants further investigation. The general and specific guidance that appears as an appendix in Supplementary data to this paper should help occupational physicians to make equitable recommendations when assessing applications for early retirement benefits and fitness to work.     

Self-reported health, illness, and self-care among finnish physicians: a national survey

BACKGROUND: Physicians' health problems have been discussed mainly in relation to substance abuse and psychiatric disorders. In this study, the prevalence of common chronic diseases and their treatment were determined. OBJECTIVE: To find differences in self-reported health status, amount of sick leave, and the use of health services among physicians according to sex and specialty. Data were also compared with those of the total employed population. DESIGN AND SETTING: Cross-sectional postal questionnaire survey in Finland. PARTICIPANTS AND METHODS: A random sample of licensed physicians younger than 66 years (n = 4477) was randomly selected from the register of the Finnish Medical Association. A total of 3313 physicians (74%) responded. MAIN OUTCOME MEASURES: Perceived health, prevalence of diseases, self-treatment of diseases, amount of sick leave, and medical consultations. RESULTS: Female physicians assessed their health as being better than other female employees and had used health services and had been on sick leave more often than their male colleagues. Male physicians assessed their health as being equal to that of other men. Both female and male physicians had fewer sick leave than other employees. However, physicians-especially men-reported many common chronic illnesses as often or more often than other employees. Physicians had consulted other medical professionals less often than other employees, and they primarily self-treated their illnesses. Of the specialties, psychiatrists had used health services and had been on sick leave more often than other physicians. CONCLUSION: This study indicates that the usual form of care of physicians' diseases is self-treatment and "working through" illnesses. Arch Fam Med. 2000;9:1079-1085     

One-year uptake of pneumococcal conjugate vaccine: a national survey of family physicians and pediatricians

BACKGROUND: Pneumococcal conjugate vaccine (PCV7) was recommended by June 2000 for administration to all US children 25% of cases of otitis media. In multivariable logistic regression analyses of adoption of PCV7, FP who have higher proportions of African American patients and patients on Medicaid, see greater numbers of newborns, work in practices of >/=4 physicians, and are willing to consider administering at least 4 vaccine injections at 1 visit are significantly more likely to have adopted PCV7. Concerns about vaccine cost and reimbursement were the most commonly cited factors in physicians' decisions not to adopt PCV7 recommendations. CONCLUSIONS: One year after PCV7 was recommended, nearly all pediatricians and a majority of family physicians had incorporated this vaccine into their practices. Barriers to higher rates of uptake-especially among family physicians-must be addressed to achieve immunization goals with this new vaccine.     

Methodologies for improving response rates in surveys of physicians: a systematic review

Although physician surveys are an important tool in health services and policy research, they are often characterized by low response rates. The authors conducted a systematic review of 66 published reports of efforts to improve response rates to physician surveys. Two general strategies were explored in this literature: incentive and design-based approaches. Even small financial incentives were found to be effective in improving physician response. Token nonmonetary incentives were much less effective. In terms of design strategies, postal and telephone strategies have generally been more successful than have fax or Web-based approaches, with evidence also supporting use of mixed-mode surveys in this population. In addition, use of first-class stamps on return envelopes and questionnaires designed to be brief, personalized, and endorsed by legitimizing professional associations were also more likely to be successful. Researchers should continue to implement design strategies that have been documented to improve the survey response of physicians.     

Attitudes and practices of Israeli physicians toward adolescent health care: a national survey.

PURPOSE: To assess practices and attitudes of Israeli physicians with regard to adolescent health. METHODS: Questionnaires were sent to a sample of 1050 Israeli physicians specializing in pediatrics (P) family practice (FP), and internal medicine (IM). They were requested to report their experience, perceived skills, and desire for further training regarding 16 adolescent health items grouped under four topics: medical, sexuality, risk behavior, and psychosocial problems. A scoring system was applied to assess their report. Attitudes toward confidentiality in the same topics were also surveyed. RESULTS: Questionnaires were received from 306 (29%) physicians, of whom 42% were P, 35% were FP, and 29% were IM. The majority (96%) of respondents included adolescents in their practice, and adolescents comprised 33%, 17%, and 11% of the registered patient population of the P, FP, and IM, respectively. The mean scores for practice, perceived skills, and desire for further training were generally low. Analysis of variance revealed significant differences among the three physicians groups in all surveyed topics, resulting from the low scores of the IM group. A diversity regarding confidentiality was noted, in that younger FP were most willing to keep health issues confidential. CONCLUSIONS: Physicians in Israel have limited experience and perceive themselves to be underskilled in dealing with adolescent health issues. Training programs in adolescent health need to be developed to meet the needs of physicians in Israel.     

Lung cancer screening practices of primary care physicians: results from a national survey

PURPOSE

Although current practice guidelines do not recommend screening asymptomatic patients for lung cancer, physicians may still order lung cancer screening tests. No recent national survey of health care professionals has focused on lung cancer screening. In this study, we examined the lung cancer screening practices of US primary care physicians and characteristics of those who order lung cancer screening tests.

METHODS

We conducted a nationally representative survey of practicing primary care physicians in 2006–2007. Mailed questionnaires assessed the physicians’ knowledge of lung cancer screening guidelines, beliefs about the effectiveness of screening tests, and ordering of screening chest radiograph, low-dose spiral computed tomography, or sputum cytology in the past 12 months. Clinical vignettes were used to assess the physicians’ intentions to screen asymptomatic 50-year-old patients with varying smoking histories for lung cancer.

RESULTS

A total of 962 family physicians, general practitioners, and general internists completed questionnaires (cooperation rate = 76.8%). Overall, 38% had ordered no lung cancer screening tests; 55% had ordered chest radiograph, 22% low-dose spiral computed tomography, and less than 5% sputum cytology. In multivariate modeling, physicians were more likely to have ordered lung cancer screening tests if they believed that expert groups recommend lung cancer screening or that screening tests are effective; if they would recommend screening for asymptomatic patients, including patients without substantial smoking exposure; and if their patients had asked them about screening.

CONCLUSIONS

Primary care physicians in the United States frequently order lung cancer screening tests for asymptomatic patients, even though expert groups do not recommend it. Primary care physicians and patients need more information about lung cancer screening’s evidence base, guidelines, potential harms, and costs to avert inappropriate ordering.     

The effect of two mailing strategies on the response to a survey of physicians

In 1989, the authors tested the effectiveness of two response-enhancing techniques, a postage stamped or franked return envelope and a prenotification letter, in a survey of pregnancy among 10,047 resident physicians in the United States. The techniques were randomly assigned using a factorial design. No significant interactions were observed between the techniques. After two mailings, those who received a stamped return envelope had a response of 71.2%, compared with 68.2% for those who received a franked return envelope (95% confidence interval 1.3-4.9%). Men who received the stamped envelope had a 5.9% greater response than those who received the franked envelope (p less than 0.001), but the type of postage did not influence response among women (p = 0.84); this interaction was statistically significant (p = 0.006). Physicians who received a prenotification letter had a response of 69.0%, compared with 70.5% for those who did not receive the letter (95% confidence interval -3.3 to 0.2%). The authors conclude that seemingly minor changes in survey design could have saved from 12% to 19% of the total cost of the study.     

Effects on subject response of information brochures and small cash incentives in a mail-based case-control study

PURPOSE: To investigate the impact on subject response of an information brochure and cash incentives included with mailed questionnaires in case-control studies. METHODS: A randomized trial was carried out within a case-control study investigating cancer in the Province of Ontario. Brochures were included with half of the mailed questionnaires sent to 7487 cases and 2561 controls. Controls were also sent cash incentives of $2, $5, or no money. RESULTS: With the brochure, response changed from 75.0% to 75.8% in cases, and from 70.3% to 71.1% in controls. Adjusting for differences in age, residence, sex, and cancer site/status, the change was 0.2% [95% confidence interval (CI) = -1.7-2.1] in cases, and 0.6% (95% CI = -3.1-4.3) in controls. The $2 and $5 incentives increased overall response in controls from 61.9% to 72.8% and 77.2%, respectively, i.e., by 10.9% (95% CI = 6.1-15.6) and 15.1% (95% CI = 10.4-19.7), after adjustment. This effect was largely confined to urban areas (for $2 and $5, respectively: 5.5% and 14.2% in Toronto, 15.3% and 20.4% in other urban areas vs. 2.7% and 1.0% in rural areas; p = 0.02). Response time showed little or no improvement when the brochure was included, but was markedly reduced for both the $2 and $5 incentives. CONCLUSIONS: Cash incentives can improve subject response in epidemiologic studies, whereas information brochures do not appear to have an effect.     

Attitudes and behaviour of general practitioners and their prescribing costs: a national cross sectional survey

Background: General practitioner (GP) prescribing accounts for about 10% of NHS expenditure. GPs at the top of the range have annual prescribing costs that are almost twice as much as those at the bottom of the range. This variation cannot be accounted for purely in terms of differences in underlying need for health care.