***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background Postal surveys are a frequently used method of data collection in health services research . Low response rates increase the potential for bias and threaten study validity . The objectives of this study were to estimate current response rates , to assess whether response rates are falling , to explore factors that might enhance response rates and to examine the potential for non-response bias in surveys mailed to healthcare professionals . Methods A r and om sample of postal or electronic surveys of healthcare workers ( 1996 - 2005 ) was identified from Medline , Embase or Psycinfo data bases or Biomed Central . Outcome measures were survey response rate and non response analysis . Multilevel , multivariable logistic regression examined the relationship between response rate and publication type , healthcare profession , country and number of survey participants , question naire length and use of reminders . Results The analysis included 350 studies .  Average response rate in doctors was 57.5 % ( 95%CI : 55.2 % to 59.8 % ) and significantly lower than the estimate for the prior 10 year period . Response rates were higher when reminders were sent ( adjusted OR 1.3 ; 95%CI 1.1 - 1.6 ) but only half the studies did this . Response rates were also higher in studies with fewer than 1000 participants and in countries other than US , Canada , Australia and New Zeal and . They were not significantly affected by publication type or healthcare profession ( p > 0.05 ) . Only 17 % of studies attempted assessment of possible non-response bias . Conclusion Response rates to postal surveys of healthcare professionals are low and probably declining , almost certainly leading to unknown levels of bias . To improve the informativeness of postal survey findings , research ers should routinely consider the use of reminders and assess potential for non-response bias Background Monetary incentives in survey research may provide important gains from a method ological perspective in the control and reduction of survey error associated with potential nonresponse of participants . However , few studies have systematic ally investigated the use of monetary incentives or other methods to improve the response rates in the nonphysician clinician population . Objective To investigate differences in response rates to a mailed self-administered survey of nonphysician clinicians who were r and omized to receive a prepaid monetary incentive , a postsurvey prize drawing , or no incentive . Methods A r and omized controlled trial of financial incentives was conducted from November 2002 to February 2003 . Nonphysician clinicians ( nurse practitioners [ NPs ] and physician assistants [ PAs ] ; N = 3,900 ) r and omly selected to participate in a national ethics-related study were assigned r and omly in equal allocations ( n = 1,300 [ 650 NPs , 650 PAs ] ) to three incentive groups : ( a ) no incentive ; ( b ) a $ 5 prepaid token incentive in the initial mailing ; or ( c ) a chance to win one of ten $ 100 prize drawings upon completion and return of a self-administered survey . Results A $ 5 cash incentive increased survey response rates to an adjusted 64.2 % : a 19.5 percentage point increase over the lottery group ( 44.7 % response rate ) , and a 22 percentage point increase over the control group ( 42.2 % response rate ) . Discussion A nominal cash incentive of $ 5 yields a significantly higher response rate from nonphysician providers than receiving either a lottery option or no incentive Background Given the increasingly stressful environment due to manpower shortages in the healthcare system in general , substance induced impairment among some healthcare professions is anticipated to grow . Though recent studies suggest that the prevalence of substance abuse is no higher in healthcare professionals ( HPs ) than the general population , given the responsibility to the public , any impairment could place the public at increased risk for errors . Few studies have ever reported predictors or risk factors for alcohol and other drug use ( AOD ) across a sample of HPs . Methods The study used a cross-sectional , descriptive self-report survey in a small northeastern state . A 7-page survey was mailed to a stratified r and om sample of 697 dentists , nurses , pharmacists and physicians registered in a northeastern state . The main outcome measures were demographic characteristics , lifetime , past year and past month prevalence of AOD use , the frequency of use , drug related dysfunctions , drug misuse and abuse potential . Six contacts during the summer of 2002 result ed in a 68.7 % response rate ( 479/697 ) . Results Risk factors contributing to any reported past year AOD use , as well as significant ( defined as the amount of AOD use by the top 25 % of respondents ) past year AOD use by HPs were examined using logistic regression . Risk factors of any self-reported past year AOD use included moderate or more frequency of alcohol use , being in situations when offered AODs , feeling immune to the addictive effects of drugs ( pharmaceutical invincibility ) and socializing with substance abusers . Risk factors of significant past year AOD use were HPs with younger licensees , a moderate pattern of alcohol use and not socializing with substance abusers . Conclusion National and state organizations need to develop policies that focus on prevention , treatment , and rehabilitation of alcohol and other drug-using healthcare professionals . The results of this study may help to delineate the characteristics of HPs abusing drugs , leading to the development of more effective policies design ed to protect the public , and move toward more tailored and effective intervention strategies for HPs The purpose of this research was to study the effect of various direct mail techniques on professional nurses '  response rates to question naires . A r and om sample of 700 registered professional nurses consisting of five groups who were members of New York State Nurses Association ( NYSNA ) were mailed a question naire with 22 items . The study demonstrated that the response rates were directly attributable to techniques used . Providing information about the association was related to significantly decreased response rates and monetary incentives with significantly increased response rates . A combined direct mailing for question naire completion and membership solicitation was not effective for either purpose The purpose was to examine the effectiveness of a modest monetary incentive ( $ 1 ) and none in increasing the response rate of a mail survey to 600 nurse practitioners . The response rate in the incentive group was 81 % and 66 % in the control group , significant by chi-square test . The most cost effective survey technique for increasing the response rate of nurse practitioners was to code the envelopes and eliminate the monetary incentive The past 20 years have seen an overall decline in survey response rates and an even more pronounced decline in sample s of health care professionals . The authors tested the use of a “ thank you ” or “ reminder ” postcard as a method by which to stem the tide of declining response rates . The authors conducted a  mail and telephone survey of 49,605 registered nurses for the 2000 National Sample Survey of Registered Nurses and sent an extra mailing to a r and om sub sample ( n= 4,968 ) . They then compared response rates for both groups . Contrary to prior research , this study found that reminder postcards did not improve response rates or rates of return . There may be several reasons for this finding , including the general familiarity with , and high saliency of , this research project for the nursing community . These results suggest that even widely accepted best practice s for survey methods deserve scrutiny when applied to special sub population OBJECTIVE To examine response rate information from  mailed physician question naires  reported in published articles . DATA SOURCES / STUDY SETTING Citations for articles published between 1985 and 1995 were obtained using a key word search of the Medline , PsychLit , and Sociofile data bases . STUDY DESIGN A 5 percent r and om sample of relevant citations was selected from each year . DATA COLLECTION / EXTRACTION METHODS Citations found to be other than physician surveys were discarded and replaced with the next r and omly assigned article . Selected articles were abstract ed using a st and ardized variable list . PRINCIPAL FINDINGS The average response rate for mailed physician question naires was 61 percent . The average response rate for large sample surveys ( > 1,000 observations ) was 52 percent . In addition , only 44 percent of the abstract ed articles reported a discussion of response bias , and only 54 percent reported any type of follow-up . CONCLUSIONS ( 1 ) Response rates have remained somewhat constant over time , and ( 2 ) research ers need to document the efforts used to increase response rates to mailed physician question naires Background : Achieving acceptable response rates from health care providers via postal question naires is an ongoing challenge . The use of monetary incentives is one of the most effective strategies for increasing response rates . However , the effect and cost of such an incentive on retail pharmacists ’ response rates has not been well studied . Methods : A sample of 700 pharmacies was selected at r and om from the electronic Yellow Pages in NSW Australia and mailed a brief survey  regarding pharmacotherapies and advice for smoking cessation . Half of the sample was r and omly allocated to receive an offer of an US$ 14 gift voucher . Results : The response rates were 65.9 % for the voucher group and 53.5 % for the no-voucher group . The odds of response from the voucher group was 1.68 ( 95%CI = 1.23 , 2.30 ) times greater than for the no-voucher group . The cost per additional respondent was US$ 67.95 . The incentive also reduced follow up costs by 10 % . Conclusions : A moderately sized monetary incentive is able to achieve a significant increase in response rates for retail pharmacists , thereby reducing potential bias in the sample Two major obstacles encountered when surveying nursing practice in institutional setting s are obtaining a representative sample and collecting an adequate number of observations at a reasonable cost . Past efforts to deal with these problems are review ed briefly , and results are reported from a two-stage mail survey of a national sample of critical-care nurses . The first stage involved attempts to procure a list of staff nurses from head nurses of critical-care units at 240 r and omly selected institutions . An 86 % response rate was obtained . The second stage involved mailing question naires to a r and om sample of 600 critical-care nurses listed . Completed , mailed question naires were obtained from 87 % . Little evidence of bias due to administrative selection and /or volunteerism was found in the lists of staff nurses . An analysis of membership in professional nursing organizations indicates that more than one half of the nurses who responded to this survey would not have been included had the sample been selected from organizational membership lists Background : Recent experiences of survey research ers suggest that physicians are becoming less willing to complete surveys . Objective : To compare response rates to a mailed physician survey with a prepaid check incentive of $ 20 versus $ 50 . Research Design : R and omized controlled trial . Subjects : Five hundred seventy-eight physicians caring for patients with lung or colorectal cancer in northern California . Measures : Proportion of physicians responding to the survey . Results : Overall , 60.0 % of physicians responded to the survey . The response rate was 52.1 % for physicians who received a $ 20 check versus 67.8 % for physicians who received a $ 50 check ( P < 0.001 ) . Similar differences in response rates were seen in strata by physician sex , year graduated from medical school , and survey version ( all P < 0.001 ) . More than 42 % of physicians who received a $ 50 check responded to the first mailing , compared with only 30.8 % of those who received a $ 20 check ( P < 0.001 ) . Conclusions : Among physicians caring for patients with lung cancer or colorectal cancer in northern California , a $ 50 check incentive was much more effective than a $ 20 check incentive at increasing response rates to a mailed survey . As physicians become increasingly burdened with surveys , larger incentives may be necessary to engage potential respondents and thus maximize response rates We conducted a pilot study to determine the most efficient mailing strategy for a postal question naire study among nurses in Ontario , Canada . Five mailing strategies involving types of stamps on the return envelopes were considered : no stamp , business-reply stamp , metered stamp , small regular stamp , and large commemorative stamp . We found that paper stamps , especially large commemorative stamps , on return envelopes increased the response rate and reduced the response time , as compared with other mailing strategies . Business-reply stamps had the lowest cost per response received and a low total cost This study assessed differences in response rates to a series of three-wave mail surveys when amiable or insistently worded postcards were the third wave of the mailing . Three studies were conducted ; one with a sample of 600 health commissioners , one with a sample of 680 vascular nurses , and one with 600 elementary school secretaries . The combined response rates for the first and second wave mailings were 65.8 % , 67.6 % , and 62.4 % , respectively . A total of 308 amiable and 308 insistent postcards were sent r and omly to nonrespondents as the third wave mailing . Overall , there were 41 amiable and 52 insistent  postcards  returned , not significantly different by chi-square test . However , a separate chi-square test for one of the three studies , the nurses ' study , did find a significant difference in favor of the insistently worded postcards To determine whether academic physicians '  response rates to a mail survey depend on the envelope used to mail the survey , we r and omized 901 internists affiliated with a university department of medicine to receive a survey  in either a university envelope or a Veterans Affairs envelope . The response rate among those receiving the Veterans Affairs envelope ( 41 % ) was 20 % higher than the response rate among those receiving the university envelope ( 34 % ) . We conclude that the packaging of a mail survey can influence the response rate Background : More patients are receiving health 
    Output:
    
Even small financial incentives were found to be effective in improving  nurse survey participation .
Token nonmonetary incentives , in contrast , 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 as well as question naires personalized and endorsed by legitimizing professional associations were also more likely to be successful .