Increasing response to a postal survey of sedentary patients - a randomised controlled trial [ISRCTN45665423]

Background

A systematic review identified a range of methods, which can influence response rates. However, analysis specific to a healthcare setting, and in particular, involving people expected to be poor responders, was missing, We examined the effect of pre-warning letters on response rates to a postal survey of sedentary patients whom we expected a low rate of response.

Methods

Participants were randomised to receive a pre-warning letter or no pre-warning letter, seven days before sending the main questionnaire. The main questionnaire included a covering letter and pre-paid return envelope. After seven days, non-responders were sent a reminder letter and seven days later, another reminder letter with a further copy of the questionnaire and return envelope.

Results

627 adults, with a mean age of 48 years (SD 13, range 18 to 78) of whom 69.2% (434/627) were women, were randomised. 49.0% (307/627) of patients were allocated to receive a pre-warning letter and 51.0% (320/627) no pre-warning letter, seven days in advance of posting the main questionnaire. The final response rate to the main questionnaire was 30.0% (92/307) amongst those sent a pre-warning letter and 20.9% (67/320) not sent a pre-warning letter, with an adjusted odds ratio of 1.60 (95% CI 1.1, 2.30).

Conclusions

The relatively low cost method of sending a pre-warning letter had a modest impact on increasing response rates to a postal questionnaire sent to a group of patients for whom a low response rate was anticipated. Investigators should consider incorporating this simple intervention when conducting postal surveys, to reduce the potential for nonresponse bias and to increase the study power. Methods other than postal surveys may be needed however when a low response rate to postal surveys is likely.     

Does telephone follow-up predict patient satisfaction and readmission?

Nursing telephone calls after hospital discharge are commonly adopted as a tool to improve patient satisfaction and continuity of care. Previous research, however, has been inconclusive on the impact of telephone follow-up. The purpose of this study was to comparatively examine patients who received telephone follow-up for response differences on a mail satisfaction survey and 30-day readmission rates for a large health system in southeast Texas. Telephone follow-up, patient satisfaction, and administrative billing data from 2008 to 2009 were retrospectively examined across 10 nursing units that routinely performed calls after patient discharge. Patients eligible to receive a nursing call (N = 10,559) were categorized based on responses to nursing questions or if no contact was made. Logistic regression was used to evaluate whether call data significantly predicted survey response and 30-day readmission rates. Nonparametric analysis was used to evaluate whether survey ratings varied between groups. Completion of telephone follow-up was a significant (P < 0.01) predictor of patient response to the mail survey, with 62% more patients returning surveys after contact. Completion of a nursing call with a patient who reported a physician appointment was a significant predictor (P = 0.04) of lower 30-day readmissions. Readmission rates were 10.8% for patients who did not receive telephone follow-up compared to 9.5% for patients who received a call and who had a scheduled physician appointment. Mean nursing and overall satisfaction scores varied minimally between groups and telephone follow-up was not a significant predictor of patient satisfaction. Telephone follow-up shows significant predictive value for mail survey response and 30-day readmission rates but does not correlate with patient satisfaction scores in the hospital setting.     

A prenotification letter increased initial response,whereas sender did not affect response rates

ObjectiveTo find ways to improve response rates of medical and health surveys. We investigated whether a prenotification letter instead of a second reminder and varying senders of the questionnaires would affect response rates.Study Design and SettingWe present the results of two studies. In the first study, four groups were compared that either received a prenotification letter (group 1 and 2) or a second reminder letter (group 3 and 4); received the questionnaire from either a research institute (group 1 and 3) or a health insurance company (HIC; group 2 and 4). In the second study, we compared two groups that received the questionnaire sent by either a HIC or a hospital. Response rates, response speed, respondent characteristics, item nonresponse, and mean scores on quality aspects and global ratings were compared.ResultsResponse rates did not differ significantly between groups. Prenotification groups returned their questionnaires faster. No other significant differences were found for response speed, respondent characteristics, item nonresponse, or mean scores.ConclusionA prenotification letter does only increase initial response speed and does not increase total response rates. A prenotification letter should be considered when quick response is desirable. Varying senders had no effect on response rates.     

Postal surveys of physicians gave superior response rates over telephone interviews in a randomized trial

BACKGROUND AND OBJECTIVES: To compare general practitioner (GP) response to a telephone interview with response to a postal survey with three reminders in a randomized controlled trial. METHODS: GPs were randomly assigned to either a telephone interview or a postal survey. GPs in the telephone group were mailed a letter of invitation and asked to undertake a telephone interview. GPs in the postal group were mailed a letter of invitation and questionnaire. Non-responders were sent up to three reminders, the final by registered post. Response rates were calculated for each group. RESULTS: 416 GPs were randomized to the telephone interview and 451 to the postal survey. Eighty-six in the telephone group and 30 in the postal were ineligible. One hundred thirty-four GPs completed the telephone interview with a response rate of 40.6% (95% confidence interval [CI]: 35.3%, 46.1%). Two hundred fifty-two GPs completed the postal survey with a response rate of 59.9% (95%CI: 55.0%, 64.6%). The difference in response was 19.3% (95%CI: 12.2%, 26.3%). CONCLUSIONS: These results show that postal surveys with three reminders can have superior response rates compared with a telephone interview.     

Labour-saving strategies to maintain survey response rates: a randomised trial

To evaluate response-aiding strategies feasible in large surveys, we randomly allocated general practitioners (GPs) to one of four intervention groups: Group 1 received 'exhaustive' telephone prompts by a medical peer in advance of a questionnaire; Group 2, inclusion of an embossed pen with the questionnaire; Group 3, an advance letter prompt; and Group 4, a 'single attempt' advance telephone prompt by a non-medical research assistant. Follow-up procedures were identical. Response rates by group were not significantly different overall (χ²4.59, df=3, p=0.20) although advance prompts by a medical peer were significantly more effective than other strategies for male GPs. The difference in overall response rates between males (63%) and females (74%) was significant (χ²=15.40, df=1, p<0.01). No other response bias was evident. Our demonstration of a significant interaction between respondent sex and response-aiding strategy invites further research.     

Women in an infertility survey responded more by mail but preferred a choice: randomized controlled trial

ObjectivesTo evaluate three modes of questionnaire completion (online, mail, and telephone) and a choice group for a questionnaire survey with a sensitive topic.Study Design and SettingA randomized trial of alternative completion methods (online, paper [mail], telephonic interview, and a choice of the three modes) for a survey about fertility problems embedded within a population-based cross-sectional survey of reproduction among women living in England and Wales.ResultsFrom an initial cohort of 21,036 women who were sent a screening questionnaire, 4,559 responded. A total of 699 women reported fertility problems, of whom 593 (85%) agreed to participate. A total of 521 (75%) of the 699 women then completed the survey. Compared with the “mail” arm, those allocated to telephonic interview were less likely to agree to participate initially (odds ratio [OR], 0.41; 95% confidence interval [CI]: 0.22, 0.74) but were ultimately more likely to complete the questionnaire (OR, 2.20; 95% CI: 1.01, 4.80). Overall, those allocated to the choice arm were most likely to go through to completion (80% vs. 77% mail, 72% telephone, and 68% online groups). In the choice arm, women showed a clear preference for mail (59% vs. 37% choosing online and 3% telephonic response).ConclusionsOnline surveys are a viable alternative to mailed questionnaires but were not as popular as mail in this study population. Response can possibly be increased by offering women a choice of response modes.     

Invitation strategies for colorectal cancer screening programmes: The impact of an advance notification letter

AimTo estimate the impact of an advance notification letter on participation in sigmoidoscopy (FS) and fecal immunochemical test (FIT) screening.MethodsEligible subjects, invited in 3 Italian population based programmes using FS and in 5 using FIT, were randomised (1:1:1), within GP, to: A) standard invitation letter; B) advance notification followed after 1 month by the standard invitation; and C) B + indication to contact the general practitioner (GP) to get advice about the decision to be screened. We calculated the 9-month attendance and the incremental cost of each strategy. We conducted a phone survey to assess GP's utilization and predictors of participation.ResultsThe advance notification was associated with a 20% increase in the attendance among 15,655 people invited for FS (B vs A — RR: 1.17, 95% CI: 1.10–1.25; C vs A — RR: 1.19, 95% CI: 1.12–1.27); the incremental cost ranged between 10 and 9 Euros. Participation in FIT screening (N = 23,543) was increased only with simple pre-notification (B vs A — RR: 1.06, 95% CI: 1.02–1.10); the incremental cost was 22.5 Euros. GP consultation rate was not increased in group C.ConclusionsAn advance notification represents a cost-effective strategy to increase participation in FS screening; its impact on the response to FIT screening was limited.     

Comparison of text-messaging to voice telephone interviews for active surveillance of adverse events following immunisation

ObjectivesIn 2013, the Follow-up and Active Surveillance of Trivalent Influenza Vaccine in Mums (FASTMum) program began using short message service (SMS) to collect adverse event information in pregnant women who recently received trivalent influenza vaccine (TIV). This study was designed to compare data collected via SMS and telephone for the purposes of monitoring vaccine safety.MethodsA number of 344 women who received TIV were randomly assigned to a telephone interview group. They were telephoned seven days post-vaccination and administered a standard survey soliciting any adverse events following immunisation (AEFI) they experienced. They were matched by brand of vaccine, age group, and residence to 344 women who were sent a SMS seven days post-vaccination. The SMS solicited similar information. AEFI reported by SMS and telephone interview were compared by calculating risk ratios.ResultsResponse rate was higher to SMS compared to telephone interview (90.1% vs. 63.9%). Women who were surveyed by SMS were significantly less likely to report an AEFI compared to women who were surveyed by telephone (RR: 0.41; 95% CI: 0.29–0.59). The greatest discrepancies between SMS and telephone interview were for self-reported injection site reactions (3.1% vs. 16.8%) and unsolicited (or “other”) events (11.4% vs. 4.1%). Data collected by SMS was significantly timelier.ConclusionsData collection by SMS results in significantly improved response rates and timeliness of vaccine safety data. Systems which incorporate SMS could be used to more rapidly detect safety signals and promote more rapid public health response to vaccine quality issues.     

Including the questionnaire with an invitation letter did not improve a telephone survey's response rate

OBJECTIVE: To determine whether including the study questionnaire with a letter of invitation improves the response rate in a telephone-based survey. STUDY DESIGN AND SETTING: This randomized controlled trial was part of a larger study to assess patient preferences for novel and controversial treatments for inflammatory bowel disease at Royal Prince Alfred Hospital, a tertiary referral teaching hospital in Sydney, Australia. RESULTS: Of 270 eligible patients, 124 (46%) were randomized to receive the questionnaire plus invitation whereas 146 (54%) were in the control group receiving a letter of invitation only. The consent rate was 26% for those receiving the questionnaire and 36% for the control group. The odds ratio for consent to participate among those sent the questionnaire to those not sent the questionnaire was 0.63 (95% CI=0.37-1.07). CONCLUSION: This study found that the advance mailing of a questionnaire to potential participants in a telephone survey reduced the likelihood of their participation.     

Format and readability of an enhanced invitation letter did not affect participation rates in a cancer registry-based study: a randomized controlled trial

ObjectivesTo assess the effectiveness of an “enhanced” invitation letter in increasing participation in an Australian cancer registry-based study and assess the representativeness of the study sample.Study Design and SettingEight hundred hematological cancer survivors, diagnosed within the last 3 years and aged 18–80 years at recruitment, were selected from one Australian state-based cancer registry. Half were randomly allocated to receive the standard invitation letter (control group). The remaining half received a modified invitation letter, incorporating content and design characteristics recommended to improve written communication (intervention group).ResultsOf the 732 eligible survivors, 268 (37%) returned a completed survey. There was no difference in participation between the intervention (n = 131, 36%) and control groups (n = 137, 38%; P = 0.53). Participants were representative of the population for characteristics assessed, except for age group at diagnosis. Survivors 50 years or older at diagnosis had higher odds of returning a completed survey, 50–59 (odds ratio [OR]: 2.53; 95% confidence interval [CI]: 1.47, 4.35), 60–69 (OR: 2.69; 95% CI: 1.58–4.58), and 70–80 (OR: 1.90; 95% CI: 1.07–3.35), than survivors aged 15–39 years at diagnosis.ConclusionAn enhanced invitation letter was not effective in increasing participation of hematological cancer survivors in an Australian cancer registry study. The study sample was moderately representative on variables assessed, with age group at diagnosis the only variable associated with participation. Research should evaluate strategies to increase participation in registry studies and focus on tailoring techniques to patient's age.     

Prenotification had no additional effect on the response rate and survey quality: a randomized trial

ObjectivesTo determine the effect of prenotification package on survey quality, including response rates, response time, percentage of nonresponse items, and cost.Study Design and SettingParticipants were randomized into two groups. In the first round mailing, participants in prenotification group received a prenotification package, whereas direct questionnaire mailing group participants received a questionnaire with prepaid return envelope only. In the second round mailing, both groups received the questionnaires. The trial was integrated into a study among 35–65-year-old female nurses in Hong Kong.ResultsA total of 367 nurses were included in the trial. A total of 362 mails were successfully delivered. The initial response rate in the first round mailing were 8.79% and 8.89% for prenotification and direct questionnaire mailing groups, respectively. After the second round mailing, the final response rate in prenotification and direct questionnaire mailing groups were 17.58% and 17.22%, respectively; no significant difference was found between the groups. There were no differences with respect to percentage of nonresponse items or response time, but the cost of prenotification group was HK$ 15.11 per response higher than direct mailing group.ConclusionPrenotification had no additional effect on the response rate and other survey quality compared with direct questionnaire mailing in a Hong Kong population.     

High Prevalence of Food Insecurity and Hunger in Households in the Rural Lower Mississippi Delta

CONTEXT: Residents of the Lower Mississippi Delta of Arkansas, Louisiana, and Mississippi are at risk for food insecurity since a high proportion of the population live in households with incomes below the poverty level and have reduced access to food and decreased availability of a variety of foods. However, the magnitude of the problem is unknown because presently only nationwide and state estimates of food insecurity are available. PURPOSE: This study was conducted by the Lower-Mississippi Delta Nutrition Intervention Research Consortium to determine the prevalence of household food insecurity, identify high-risk subgroups in the Lower Delta, and compare to national data. METHODS: A 2-stage stratified cluster sample representative of the population in 36 counties in the Lower Delta was selected using list-assisted random digit dialing telephone methodology. A cross-sectional telephone survey of 1662 households was conducted in 18 of the 36 counties using the US Food Security Survey Module. FINDINGS: Twenty-one percent of Lower Delta households were food insecure, double the 2000 nationwide rate of 10.5%. Within the Lower Delta, groups with the highest rates of food insecurity were households with income below $15,000, black households, and households with children. The prevalence of hunger in Delta households with white children was 3.2% and in households with black children was 11.0%, compared to nationwide estimates of 0.3% and 1.6%. CONCLUSIONS: The Lower Mississippi Delta is characterized by a high prevalence of food insecurity and hunger. Future efforts to identify the household and community determinants of food insecurity to reduce its high prevalence are indicated.     

Combining conditional and unconditional recruitment incentives could facilitate telephone tracing in surveys of postpartum women

BACKGROUND AND OBJECTIVE: To compare tracing and contact rates using alternative incentives in a computer-assisted telephone interview (CATI) survey among postpartum women. METHODS: In a randomized trial of 1,061 postpartum women 18-49 years of age selected from four Iowa counties, we compared the effects of: (1) unconditional $5 telephone card incentive enclosed with the introductory letter followed by $25 incentive conditional upon successful telephone tracing, contact, and completion of CATI (Group 1, n = 530) vs. (2) $30 incentive conditional upon subject completion of CATI (Group 2, n = 531). RESULTS: Overall telephone tracing and contact rates achieved were 67.8% and 66.6%, respectively. Tracing (70.2 vs. 65.4%, P = .09) and contact (68.5 vs. 64.8%, P = .26) rates were consistently higher among subjects assigned the combination of a conditional and an unconditional incentive. The combined incentive type had a greater impact on telephone tracing success rates for subjects on whom we could not initially locate an active telephone number (16.7 vs. 7.3%, P = .07) when compared to subjects for whom we found an active telephone number at the time of mailing the introductory letter (78.9 vs. 75.9%, P = .30). CONCLUSIONS: Combining conditional and unconditional recruitment incentives can facilitate telephone tracing efforts in surveys conducted among recently postpartum women.     

Promoting mammography use through progressive interventions: is it effective?

This study evaluated interventions implemented with women in a health maintenance organization who had not utilized their annual free mammogram referral 45 days (step 2) and 95 days (step 3) after its mailing. The step 2 evaluation compared mammography utilization for women randomly assigned to receive a brief reminder letter or no reminder: 42% of the reminder group vs 28% of the control group obtained mammograms. The step 3 evaluation compared utilization for women randomly assigned to receive a second reminder, a letter suggesting a preventive office visit, or telephone counseling: 29% of those who received telephone counseling, 14% of those who received a letter, and 12% of those who received a second reminder obtained mammograms.     

Do parents prefer inactivated or live attenuated influenza vaccine for their children?

ObjectivesTo determine the proportion of children whose parents prefer them to receive live, attenuated influenza vaccine (LAIV) or inactivated influenza vaccine (IIV), examine reasons for preferences, and determine what percentage of vaccinated children receive other than the preferred type of vaccine and why.MethodsParental-reported data for the 2014–15 and 2015–16 influenza seasons from the National Immunization Survey-Flu (NIS-Flu), a random-digit-dialed, dual frame (landline and cellular telephone) survey of households with children, were analyzed. We calculated the proportions of vaccinated children aged 2–17 years whose parents preferred LAIV, IIV, or had no preference, and the proportions that were vaccinated with other than the preferred type of vaccine.ResultsFor the 2014–15 and 2015–16 seasons, 55.2% and 53.7%, respectively, of vaccinated children had parents who reported no preference for either IIV or LAIV. The percentage who preferred LAIV was 22.7% and 21.7%, and IIV was 22.1% and 24.7%. The most common reason given by parents for preferring LAIV was the child’s fear of needles (70.9%) and for preferring IIV was belief that the shot is more effective (29.0%). Approximately one-third of vaccinated children whose parents preferred LAIV received IIV only.ConclusionsThe main finding of this study was that most parents do not have a vaccine type preference for their children. The lack of overwhelming preference is advantageous for the maintenance of vaccination coverage levels during times when one vaccine type is not available or not recommended such as in the 2016–17 and 2017–18 seasons when there was a temporary recommendation not to administer LAIV.     

Increasing response rates of gynaecologists to a survey: a randomised trial of telephone prompts

Abstract: This study used a randomised controlled trial to evaluate the effectiveness of telephone prompts to increase the response rate of gynaecologists to a survey. A nine-page questionnaire about management of women with abnormal Pap smears was mailed to Fellows of the Royal Australian College of Obstetricians and Gynaecologists. A random sample was contacted in advance by telephone, and nonrespondents received a telephone reminder 14 days after the initial mail-out. The control group was mailed questionnaires and a reminder letter conventionally. On Day 25, nonresponders in both groups were mailed a second questionnaire. Of the intervention group, 84 per cent responded to the survey compared to 69 per cent of the control group (P = 0.005). A telephone call in anticipation of a mailed questionnaire is highly recommended.     

The experience of using random digit dialling methods in a population-based chronic pain study

OBJECTIVES: To describe response rates and call characteristics using random digit dialling (RDD) methods in a population-based prevalence study of chronic pain; to compare respondent characteristics according to telephone number listing status. METHODS: A RDD telephone study of chronic pain was conducted using computer-assisted telephone interview (CATI) methods in the Northern Sydney Area in 1998. RESULTS: Unlisted number respondents (18.5%) were younger, had a higher proportion of males, and were less likely to live in households with three or more eligible adults. There was no difference in chronic pain status between the two groups. The overall response rate was 73.4% (unlisted number group 66.3%; listed number group 75.0%). Answering machine messages boosted response rates (79.7%). 10.9% of unlisted numbers used in the study resulted in completed interviews, compared with 31.3% of the listed numbers used. CONCLUSIONS: The relatively high response rate obtained, differences in characteristics associated with listing status and reduction in sampling bias provided by using RDD methods have to be balanced against the differential response rates between listed and unlisted number groups and higher costs (including opportunity costs). IMPLICTIONS: Published data on the experience of using RDD methods can assist public health researchers in deciding whether to use these methods in telephone surveys.     

A randomized trial of opinion leader endorsement in a survey of orthopaedic surgeons: effect on primary response rates

BACKGROUND: Opinion leaders have been shown to have significant influence on the practice of health professionals and patient outcomes. METHODS: Using focus groups, key informants, and sampling to redundancy techniques, we developed a questionnaire of surgeons' preferences in the treatment of tibial shaft fractures. Twenty-two well-respected and widely known orthopaedic traumatologists endorsed the questionnaire. We randomized 395 surgeon members of the Orthopaedic Trauma Association to receive either a questionnaire that included a letter informing them of the opinion leaders' endorsement, or a questionnaire without the endorsement. RESULTS: Surgeons who received the letter of endorsement had a significantly lower response rate at 2, 4, and 8 weeks. The absolute difference in response rates was 7.8% (4.6% versus 12.4%, P < 0.05) at 2 weeks, 13.1% at 4 weeks (28.6% versus 41.7% P < 0.02), and 12.3% at 8 weeks (47.5% versus 59.8% P = 0.02). CONCLUSIONS: The addition of a letter listing expert surgeons who endorse the survey lead to significantly lower primary response rates. Those interested in influencing physician responses cannot always assume a positive effect from endorsement by opinion leaders     

Analysis of Differences in Preterm Birth Rates According to Household Occupation in Japan From 2007 to 2019

ObjectivesNo studies have examined the association between preterm birth rates and socioeconomic factors in Japan using nationwide statistical data. We analyzed the association between preterm birth rates and household occupation using Vital Statistics data.MethodsAggregated Vital Statistics data from Japan from 2007 to 2019 were obtained from the Ministry of Health, Labour and Welfare. From the data, the number of births according to year, age group, gestational period, number of pregnancies, and household occupation were used in this study. Crude preterm birth rates and preterm birth rates adjusted by maternal age according to household occupation were calculated for each year. Poisson regression analysis was conducted to evaluate the association between household occupation and preterm births.ResultsUnemployed households had the highest preterm birth rate, and households with an occupation classification of “full-time worker 2” (an employee at a large company, civil servant, or board member) had the lowest preterm birth rate throughout each period. Poisson regression analysis revealed that unemployed households were statistically significantly associated with a high preterm birth risk. In contrast, the preterm birth rate adjusted by maternal age remained stable throughout each period regardless of household occupation, and preterm birth rates were found not to have increased in recent years in Japan.ConclusionsUnemployed households had higher preterm birth rates than other household occupations. Further studies investigating the characteristics of unemployed households are needed to identify the reasons for this disparity.     

Effect of survey instrument on participation in a follow-up study: a randomization study of a mailed questionnaire versus a computer-assisted telephone interview

ABSTRACT: BACKGROUND: Many epidemiological and public health surveys report increasing difficulty obtaining high participation rates. We conducted a pilot follow-up study to determine whether a mailed or telephone survey would better facilitate data collection in a subset of respondents to an earlier telephone survey conducted as part of the National Birth Defects Prevention Study. METHODS: We randomly assigned 392 eligible mothers to receive a self-administered, mailed questionnaire (MQ) or a computer-assisted telephone interview (CATI) using similar recruitment protocols. If mothers gave permission to contact the fathers, fathers were recruited to complete the same instrument (MQ or CATI) as mothers. RESULTS: Mothers contacted for the MQ, within all demographic strata examined, were more likely to participate than those contacted for the CATI (86.6% vs. 70.6%). The median response time for mothers completing the MQ was 17 days, compared to 29 days for mothers completing the CATI. Mothers completing the MQ also required fewer reminder calls or letters to finish participation versus those assigned to the CATI (median 3 versus 6), though they were less likely to give permission to contact the father (75.0% vs. 85.8%). Fathers contacted for the MQ, however, had higher participation compared to fathers contacted for the CATI (85.2% vs. 54.5%). Fathers recruited to the MQ also had a shorter response time (median 17 days) and required fewer reminder calls and letters (median 3 reminders) than those completing the CATI (medians 28 days and 6 reminders). CONCLUSIONS: We concluded that offering a MQ substantially improved participation rates and reduced recruitment effort compared to a CATI in this study. While a CATI has the advantage of being able to clarify answers to complex questions or eligibility requirements, our experience suggests that a MQ might be a good survey option for some studies.