Introduction
Methods
Protocol and registration
Eligibility criteria
Inclusion criteria
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Types of population: This study followed Edwards et al. (2009) in using data from “[a]ny population (e.g. patients or healthcare providers and including any participants of non-health studies).” This should maximise generalisability over different contexts.
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Types of interventions: interventions must include some type of questionnaire pre-contact (pre-notification, advance letter/email/text/phone call or other co-referring term). No restriction is placed on the type of questionnaire pre-notification.
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Comparison group: Included studies need to be able to make a direct comparison of the effect of questionnaire pre-notification vs no pre-notification (i.e. include at least one arm which received identical treatment to the pre-notification arm other than not receiving the pre-notification).
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Types of outcome measures: The proportion or number of completed, or partially completed questionnaires returned after all follow-up contacts were complete.
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Types of study design: Any randomised control trial evaluating a method of advanced contact to increase response to questionnaires. The inclusion of only randomised control trials should on average eliminate risk of confounding biasing estimates within studies.
Exclusion criteria
Information sources
Study selection
Data collection process
Data items
Risk of bias in individual studies
Summary measures, and planned methods of results synthesis
Risk of bias across studies
Assessment of certainty in the body of evidence
Results
Study section
Study characteristics
Citation | Comparison | Outcome definition | Design | Setting (Country) | Topic | Delay Length | Pre-Contact Method | Survey Delivery | Foot-in-the-door? |
---|---|---|---|---|---|---|---|---|---|
Bergen 1957 [16] | Pre-contact or Control | final follow-up | experiment | primary school teachers (Netherlands) | options and attitudes towards public opinion researcher | mail | Postal | have to return a pre-paid return card | |
Albaum 1989 [17] | (Pre-contact or Control)x(leaflet or control) | final follow-up | factorial experiment | Business firms who do international market activities. (Denmark) | questions about work | mail | Postal | send description | |
Drummond 2008 [18] | (Pre-contact vs Control) x(questionnaire or control) | final follow-up | factorial experiment | GPs. (Ireland) | Health: views and practices about prostate-specific testing (PSA) | 3 weeks | mail | Postal | none stated |
Napoles-Springer 2004 [19] | Pre-contact or Control | final follow-up | Randomised control trail. | Nested in satisfaction survey of ambulatory care clinics. Have to use primary care and be older than 50 (USA) | about hospital experience year before/stratification | 2 weeks | mail | Postal | none stated |
Newby 2003 [20] | Pre-contact, Control, colour follow up, or monetary incentive | first and final follow-up | Randomised control trail. | random sample of business in Perth. exclude gov. enterprises and publicly owned firms (Australia) | about business: expectations and attitudes of the self employed | 2 weeks | telephone | Postal | Asked relevant questions |
Ogbourne 1986 [21] | Pre-contact or Control | first and final follow-up | Randomised control trail. | health and social workers (Canada) | about work | telephone | Postal (phone option in intervention) | offer a telephone interview if better than mail | |
Whiteman 2003 [22] | ×2 types of incentives, Pre-contact or Control | first and final follow-up | Randomised control trail. | women age 40–60 and in Baltimore (USA) | women’s health | 1 week | mail | Postal | none stated |
Cycyota 2002 [23] | (Pre-contact or Control) x(incentive or cont.) x (personalisation or cont.) x(follow-up or cont.) x (postage or cont.) | final follow-up | factorial experiment | chamber of commerce survey to business (USA) | business climate | 2 weeks | mail | Postal | none stated |
Childers 1979 [24] | ×2 types Pre-contact or Control | final follow-up | Randomised control trail. | agents of a large Midwest-based insurance company (USA) | insurance | mail | Postal | one group given return cards | |
Eaker 1998 [25] | (Pre-contact or Control) x (length or control) x (mention of telephone contact or control) | final follow-up | factorial experiment | Men and women living in Sweden in 1995 20–79 yrs. Old (Sweden) | health risk factors | 1 week | mail | Postal | none stated |
Etter 1998 [26] | (Pre-contact or control) x (layout or control) | first and final follow-up | factorial experiment | annual insurance questionnaire; residents of Geneva, valid address (Switzerland) | health insurance survey | 2 weeks | mail | Postal | none stated |
Ford 1967 A [27] | Pre-contact or control | first and final follow-up | experimental design | Residents of Chenoa (USA) | shopping survey | 1 week | mail | Postal | none stated |
Ford 1967 B [27] | Pre-contact or control | first and final follow-up | experimental design | Residents of Beardstown (USA) | shopping survey | 1 week | mail | Postal | none stated |
Hansen 1980 [28] | ×2 Pre-contact, questionnaire length, or control | final follow-up | Randomised control trail. | People who bought cars in past year in Ohio (USA) | consumer’s attitudes towards recent new car purchases | 3 days | telephone | Postal | Asked if willing to enter study. |
Harrison 2004 [29] | Pre-contact or control | final follow-up | Randomised control trail. | patients referred to exercise referral scheme in past 12 months by primary care ( | survey on relation between service expectations and outcomes | 1 week | mail | Postal | none stated |
Hornik 1982 [30] | Pre-contact or control | final follow-up | Randomised control trail. | Sample from telephone directly (USA) | about TV/advertising | under 1 week | telephone | Postal | none stated |
Kephart 1958 [31] | Pre-contact or control | first and final follow-up | experiment | women who had taken state nursing exam in 1950 (USA) | Attitudes towards nursing profession | 1 week | mail | Postal | none stated |
Mann 2005 [32] | Pre-contact or control | final follow-up | experiment | registered voters in 3 states (USA) | election survey | mail | telephone | none stated | |
Parsons 1972 A [33] | Pre-contact or control | only one mailing | experiment | MBA alumni (USA) | politics and religion | 4 days | mail | Postal | none stated |
Parsons 1972 B [33] | Pre-contact or control | only one mailing | experiment | leaders of 2 religious sects (USA) | politics and religion | 5 days | mail | Postal | none stated |
Pirotta 1999 [34] | Pre-contact or control | first and final follow-up | Randomised control trail. | GPs. From health insurance In Victoria; have to have had 1500 consultations in prior year (Australia) | work | 5 days | mail | Postal | ask for prompt return |
Shiono 1991 [35] | Pre-contact or control | first and final follow-up | Randomised control trail. | physician who graduated from med school in 1985 (USA) | survey of pregnancy in physicians. Mailed was personalised | 1 week | mail | Postal | toll free phone number to call if any questions about the survey |
Spry 1989 [36] | Pre-contact or control × 3 | first and final follow-up | factorial experiment | residence of San Diego (USA) | survey on health related behaviour. Enrolments from medical school director | under 1 week | phone or post card | Postal | none stated |
Wiseman 1972 [37] | 2 types of Pre-contact or control | final follow-up | experiment | residents of Boston (USA) | political issue polling | under 1 week | Telephone or mail | Postal | describes survey |
Dillman 1974 [38] | Pre-contact or control | final follow-up | Randomised control trail. | sample of general public (USA) | feelings and concerns about Washington State University | na | telephone | Postal | ask questions to raise salience |
Furst 1979 [39] | (Pre-contact or control) x (Personalisation or contorl) | final follow-up | factorial experiment | head teachers (USA) | personality test | under 1 week | mailed | Postal | none stated |
Gillpatick 1994 [40] | (Pre-contact or control) x (2 types of monetary incentive or control) | only one mailing | factorial experiment | engineers who subscribe to a trade journal (USA) | market research (how good a CAD program is). One condition is personally pre-contacted, the other gets a referral from a colleague | Postal | none stated | ||
Heaton 1965 [41] | Pre-contact or control | only one mailing | experiment | people who bought a Chevrolet in Philadelphia | car sales survey. Attempt to show importance of survey. Also personalised (e.g. hadn’t signed) | 1 week | mailed | Postal | none stated |
Jobber 1985 [42] | Pre-contact or control | final follow-up | Randomised control trail. | UK textile companies executives | Explore the design and extent of implementation of marketing information system | telephone | Postal | none stated | |
Jobber 1983 [43] | (Pre-contact or control) x (colour or control) | first and final follow-up | factorial experiment | UK textile companies | marketing practices | mailed | Postal | none mentioned | |
Kindra 1985 [44] | (Pre-contact or control) x (incentive or control) | first and final follow-up | factorial experiment | telephone directory (Canada) | response to advertising | telephone | Postal | Asked questions in pre-contact | |
Myers 1969 [45] | follow up, Pre-contact or control | only one mailing | Randomised control trail. | telephone directory (USA) | reaction to bank advertisement | 1 week | mailed | Postal | none stated |
Nichols 1988 [46] | Pre-contact or control) | final follow-up | Randomised control trail. | sample of electoral role (UK) | mailed was a leaflet on nutrition + cover mailed | 5 weeks | mailed | Postal | none stated |
Osborne 1996 [47] | Pre-contact or control | first and final follow-up | Randomised control trail. | GPs (Australia) | view on pathology test | telephone | Postal | none stated | |
Pucel 1971 [48] | Pre-contact or control | only one mailing | Randomised control trail. | graduates from 24 post-high schools (USA) | effect of training | 1 week | mailed | Postal | none stated |
Duhan 1990 [49] | Pre-contact or control | first and final follow-up | Randomised control trail. | marketing executives (USA) | work related | 1 week | mailed | Postal | Asked questions |
Faria 1990 [50] | ×2 types of Pre-contact or control | first and final follow-up | Randomised control trail. | Homeowners residing on the property owners’ listing (USA) | under 1 week | phone or mailed | Postal | Asked if they will participate | |
Stafford 1966 [51] | ×2 types of Pre-contact or control | only one mailing | Randomised control trail. | students (USA) | collegiate clothing | under 1 week | phone or mailed | Postal | none stated |
Sutton 1992 [52] | (personalisation or control) x (Pre-contact or control) | first and final follow-up | factorial experiment | customers of a utility company, and contractors (USA) | reaction to an established energy rebate program | 10–14 days: phone, 1 week: card | mailed | Postal | none stated |
Taylor 1998 [53] | Pre-contact or control | first and final follow-up | Randomised control trail. | Young people in the Youth Cohort Study 8 sample, (UK) | Attitudes and behaviour | 1 week | mailed | Postal | none stated |
Martin 1989 [54] | (Pre-contact or control) x (follow up or control) x (personalisation or control) x (cover mailed or control) x (return postage or control) | final follow-up | factorial experiment | students in an urban university (USA) | views on the university | mailed | postal | none stated | |
Chebat 1991 [55] | (Pre-contact or control) x (incentive or control) | final follow-up | factorial experiment | The Quebec population within the legal driving age (Canada) | Postal | none stated | |||
Xie 2013 [56] | Pre-contact or control | final follow-up | Randomised control trail. | female nurses, age 35–65. with correct contact information (Hong Kong) | work and health | 1 week | mail | Postal | asked to send reply slip |
Mitchell 2012 [57] | Pre-contact or control | final follow-up | Randomised control trail. | nested in follow up of the SCOOP clinical trial. Women aged between 70 and 84, at high risk of osteoporotic features (UK) | Trail questions | 6 weeks | mail | Postal | none stated |
Maclennan 2014 [58] | Pre-contact or control | first and final follow-up | Randomised control trail. | nested in RECORD clinical trial. Patients who had not responded to annual follow ups. Over 70, history of fracture, not in other methodological study (UK) | self-reported fracture and quality of life | ≥ two weeks | telephone | Postal | none stated |
Keding 2016 [59] | Pre-contact or control | only one mailing | Randomised control trail. | nested in ACUDep trial, primary care patients in N England. Have mobile phone | quality of life | 4 days | sms | Postal | none stated |
Hammink 2010 [60] | (Pre-contact or control) x (follow up or control) | first and final follow-up | factorial experiment | nested in survey of GP patients (Netherlands) | quality of care/experience | 1 week | mail | Postal | none stated |
Felix 2011 [61] | (Pre-contact or control) x (tone or control) | only one mailing | factorial experiment | authors of published maternal health research (UK) | applying their research to LIC | 1 week | email | online | none stated |
Bauman 2016 [62] | (Pre-contact or control) x (follow up or control) | first and final follow-up | factorial experiment | nested in 45 and Up Study. adults 45 to 100 living in New South Wales. (Australia) | socio-environmental causes of health | 2 weeks | mail | Postal | none stated |
Barra 2016 [63] | Pre-contact or control | first and final follow-up | Randomised control trail. | patients discharged in stated time who had not responded to previous survey, involved in other studies/care and had a phone number (Norway) | post stroke questionnaire | 1 week | mail | Postal | ask for consent to receive survey |
Bosnjak 2008 [64] | (×2 types Pre-contact or control) x (invitation or control) | final follow-up | factorial experiment | university students (Germany) | psychometrics, e.g. personality test | 1 week | email or sms | online | none stated |
Boyd 2015 [65] | (Pre-contact or control) ×2 follow up or control) x (design or control) | final follow-up | factorial experiment | ALSPAC follow up (UK) | consent to patients in follow up. | 1 week | mail | Postal | none stated |
Dykema 2011 [66] | (Pre-contact or control) x (incentive or control) | final follow-up | factorial experiment | physicians, (USA) | assess knowledge of genetic variation. | 1 week | mail | online | none stated |
Grande 2016 [67] | Pre-contact or control | only one mailing | Randomised control trail. | Random digit dialling (Australia) | epidemiological facts about the workplace | same day | sms | phone | none stated |
Mclean 2014 [68] | (Pre-contact or control) x (design or control) | only one mailing | factorial experiment | the electoral roll (Australia) | 1 week | mail | Postal | none stated | |
Rao 2010 [69] | (Pre-contact or control) x (follow up or control) x (incentive or control) x (recurrent mode or control) | final follow-up | factorial experiment | Random digit dialling | opinion poll survey | 1 week | mail | Postal | none stated |
Starr 2015 [70] | (Pre-contact or control) x (follow up or control) | final follow-up | factorial experiment | nested in epilepsy rct, provided phone number (UK) | under a week | sms | Postal | none stated | |
van Veen 2016 [71] | ×2 types Pre-contact or control | only one mailing | Randomised control trail. | university students (Germany) | cheating in exams | 1 week | mail | online | none stated |
Ho-A-Yun 2007 [72] | Pre-contact or control | only one mailing | Randomised control trail. | GPs in Scotland (UK) | under a week | telephone | Postal | none stated but uses phone to call receptionist | |
Porter 2007 A [73] | (×2 types Pre-contact or control) x (follow up or control) | final follow-up | factorial experiment | high school students who contacted liberal arts college but did not apply (USA) | perceptions of college | 1 week | email or post | online | none stated |
Porter 2007 B [73] | (×2 types Pre-contact or control) x (follow up or control) | final follow-up | factorial experiment | alumni of liberal arts collage (USA) | career post-graduation | 1 week | email or post | online | none stated |
Atinc 2012 [74] | (Pre-contact or control) x (follow up or control) | final follow-up | factorial experiment | university staff and faculty (USA) | under a week | email | online | none stated | |
Walker 1977 [75] | Pre-contact or control | only one mailing | Randomised control trail. | credit card holders (USA) | consumer credit survey/purchase history | under a week | mailed | mail | none stated |
Snow 1986 [76] | Pre-contact or control | final follow-up | Randomised control trail. | People existing job training partnership program (USA) | outcome of state-wide job training program | 1.5 weeks | mailed | phone | none stated |
Pitiyanuwat 1991 [77] | (Pre-contact or control) x (deadline or control) x (design or control) | first and final follow-up | factorial experiment | public school teachers, (Thailand) | desirable characteristics of a teacher | mailed | mail | none stated | |
Nicolaas 2015 [78] | (Pre-contact or control) x (follow up or control) x (design or control) | final follow-up | factorial experiment | embedded in a GP patient survey: over 18, registered with GP for >6mths (UK) | expense of patients of the NHS | 1 week | mailed | mail | none stated |
Link 2005 [79] | Pre-contact or control | only one mailing | Randomised control trail. | House holds in Behaviour Risk Factor Survey (USA) | health behaviours | under a week | mailed | phone | none stated |
Kulka 1981 [80] | (Pre-contact or control) x (incentive or control) x (extra follow up or control) x (postage or control) | final follow-up | factorial experiment | registered nurses enrolled in a survey (USA) | 2 weeks | mailed | mail | none stated | |
Kaplowitz 2004 [81] | Pre-contact or control | final follow-up | Randomised control trail. | university students (USA) | mailed | email | none stated | ||
Groves 1987 [82] | X3 types of Pre-contact or control | only one mailing | Randomised control trail. | nested in NHIS survey (USA) | Health care | mailed | phone | none stated | |
Furse 1981 [83] | Pre-contact, incentive or control | final follow-up | Randomised control trail. | Tennessee population (USA) | phone | mail | none stated | ||
Chebat 1993 [84] | (questionnaire type or control) x (Pre-contact, incentive or control) | first and final follow-up | factorial experiment | (Canada) | 2 weeks | mailed | mail | none stated | |
Boser 1990 [85] | (Pre-contact or control) x (follow up or control) | final follow-up | factorial experiment | Graduates (USA) | emphasise value of participation | 1 week | mailed | mail | none stated |
Bergsten 1984 [86] | Pre-contact or control | only one mailing | Randomised control trail. | Medicare beneficiaries 65+ (USA) | access to health care | 1 week | phone | interview | arrange time for interview |
Baulne 2009 [87] | Pre-contact or control) | only one mailing | Randomised control trail. | people over 15 and live in a household. (Canada) | health | mail | phone | none stated | |
Henri 2012 [88] | X2 types Pre-contact or control | final follow-up | Randomised control trail. | listed companies (Canada) | management accounting research | 2 weeks | telephone or mail | mail | none stated |
Lalasz 2014 [89] | Pre-contact or control | final follow-up | Randomised control trail. | alumni 1 year post graduation (USA) | graduate careers etc. | 2 weeks | mail | online | none stated |
von der Lippe 2011 [90] | Pre-contact or control | only one mailing | Randomised control trail. | nested in German Health Update Survey 2009. | health | 2 weeks | mail | phone | none stated |
Lusinchi 2007 [91] | Pre-contact or control | first and final follow-up | Randomised control trail. | electrical engineers (USA) | under a week | email | online | none stated | |
McCallister 2008 [92] | X2 types Pre-contact or control | first and final follow-up | Randomised control trail. | university staff (USA) | under a week | post or email | mail | none stated | |
Miner 1983 [93] | X2 types Pre-contact or control | final follow-up | Randomised control trail. | parents/carers of people who had used a child psychiatry unit (USA) | under a week | post or phone | mail | none stated | |
Mitchell 2012 [57] | (Pre-contact or control) x (follow up or control) | only one mailing | factorial experiment | Academics in Northern UK | 6 weeks | mail | mail | none stated | |
Steeh 2007 [94] | sms + called back (passive), sms + user has to call (active) or control | only one mailing | Randomised control trail. | Nexel subscribers. (USA) | Under 1 week | sms | phone | one treatment group have to call rather than be called to do interview | |
Vogl 2018 [5] | Pre-contact or control | only one mailing | Randomised control trail. | Random digit dialling (Germany) | Partner violence | 1 week | mail | phone | none stated |
Woodruff 2006 [95] | Pre-contact or control | final follow-up | Randomised control trail. | Random digit dialling (USA) | info about study/importance of patients. Parents/children for NIH study on teenage health | 2 weeks | mail | phone | none stated |
Traugott 1993 [96] | Pre-contact or control | only one mailing | Randomised control trail. | Random digit dialling (USA) | mailed | phone | none stated | ||
(Pre-contact or control) x (personalisation or control) | only one mailing | factorial experiment | Random digit dialling (USA) | mailed | phone | none stated | |||
Brehm 1994 [99] | inactive + Pre-contact, Pre-contact, logo, or control | only one mailing | Randomised control trail. | Random digit dialling (USA) | Attitudes to war | 1–2 weeks | mailed | phone | none stated |
Camburn 1995 [100] | X3 types Pre-contact or control | final follow-up | Randomised control trail. | Random digit dialling (USA). Non house hold and non-working numbers excluded | child immunisation | mailed | phone | none stated | |
Dillman 1976 [101] | Pre-contact or control | only one mailing | Randomised control trail. | Random digit dialling (USA) | mailed | phone | none stated | ||
Eyerman 2003 [102] | Pre-contact or control | only one mailing | Randomised control trail. | Random digit dialling (USA) | Health risk factors | under a week | mailed | phone | none stated |
Goldstein 2002 [103] | Pre-contact or control | final follow-up | Randomised control trail. | Random digit dialling (USA) | Political polling | under a week | mailed | phone | none stated |
Hembroff 2005 [104] | X2 types Pre-contact or control | final follow-up | Randomised control trail. | Random digit dialling (USA) | Mailed | phone | none stated | ||
Iredell 2004 [105] | Pre-contact or control | final follow-up | Randomised control trail. | electoral roll. Have to be over 60 (Australia) | road crossing behaviour | 2 weeks | mailed | phone | none stated |
Mickey 1999 [106] | (Pre-contact or control) x (survey administration or control) | final follow-up | factorial experiment | over 40 (USA) | one week | mailed | in person or phone | none stated | |
Smith 1995 [107] | Pre-contact or control | only one mailing | Randomised control trail. | Random digit dialling (Australia). Exclude if non residential household, or non English speaking | health questions | mailed | phone | none stated | |
Singer 2000 [108] | Pre-contact or control | only one mailing | Randomised control trail. | Random digit dialling (USA) | consumer attitudes | mailed | phone | none stated | |
Gerritsen 2002 A [109] | Pre-contact or control | final follow-up | Randomised control trail. | Random digit dialling (Netherlands) | meat consumption, non-commercial | one week | mailed | phone | none stated |
Gerritsen 2002 B [109] | Pre-contact or control | final follow-up | Randomised control trail. | people who had not answered their phone | meat consumption, non-commercial | one week | answer phone message | phone | none stated |
Brick 1997 [110] | Pre-contact or control | final follow-up | Randomised control trail. | Random digit dialling (USA) | mailed | phone | Asked questions | ||
Goulao 2020 [111] | Pre-contact or control | final follow-up | Randomised control trail. | Scotland | dentist patients | under a week | Postal | Postal | none stated |
Rodgers 2018 [112] | Pre-contact or control | final follow-up | Randomised control trail. | UK | RCT outcomes | under a week | Postal | Postal | none stated |
Sakshaug 2019 [113] | Pre-contact or control | final follow-up & before | Randomised control trail. | Germany | companies | one week | Postal | Email | Had to send an email |
von Allmen 2019 [114] | Pre-contact or control | final follow-up | Randomised control trail. | Switzerland | aneurysm repairs | under a week | Postal | Phone | none stated |
Griggs 2019 [115] | Pre-contact or control | final follow-up | Randomised control trail. | USA | Add Health wave V | under a week | Postal | Online | none stated |
Vogl 2019 [116] | Pre-contact or control | final follow-up | Randomised control trail. | Germany | Violence survey | under a week | Postal | Phone | none stated |
Gooden 2021 [117] | Pre-contact or control | final follow-up | Randomised control trail. | UK | mental health survey | under a week | Postal | Postal | none stated |