Table 1

Electronic bibliographical databases and search strategies used in systematic review of response to postal questionnaires

Database (time period or version)Search strategy
With study type filters of known sensitivity and positive predictive value:
  CINAHL (1982-07/1999) Cochrane Controlled Trials Register (1999.3) Dissertation Abstracts (1981-08/1999) Embase (1980-08/1999) ERIC (1982-09/1998) Medline (1966-1999) PsycLIT (1887-09/1999)A. questionnair* or survey* or data collection B. respon* or return* C. remind* or letter* or postcard* or incentiv* or reward* or money* or monetary or payment* or lottery or raffle or prize or personalis* or sponsor* or anonym* or length or style* or format or appearance or color or colour or stationery or envelope or stamp* or postage or certified or registered or telephon* or telefon* or notice or dispatch* or deliver* or deadline or sensitive D. control* or randomi* or blind* or mask* or trial* or compar* or experiment* or “exp” or factorial E. A and B and C and D
Without study type filters of known sensitivity and positive predictive value:
  Science Citation Index (1980-1999) Social Science Citation Index (1981-1999)(survey* or questionnair*) and (return* or respon*)
  Social Psychological Educational Criminological   Trials Register (1950-1998)(survey* or questionnair*) and (return* or respon*)
  EconLit (1969-2000) Sociological Abstracts (1963-2000)((survey$ or questionn$) and (return$ or respon$)).ti or ((survey$ or questionn$) and (mail$ or post$)).ti or ((return$ or respon$) and (mail$ or post$)).ti
  Index to Scientific and Technical Proceedings   (1982-2000)((survey*, questionn*)+(return*,respon*))@TI,((return*,respon*)+ (mail,mailed,postal))@TI, ((survey*,questionn*)+(mail,mailed,postal))@TI
  National Research Register (Web version: 2000.1)((survey*:ti or questionn*:ti) and (return*:ti or respon*:ti)) or ((return*:ti or respon*:ti) and (mail:ti or mailed:ti or postal:ti)) or ((survey*:ti or questionn*:ti) and (mail:ti or mailed:ti or postal:ti))
  • Search strategies were developed to achieve a balance between sensitivity and positive predictive value.

  • † Highly sensitive subject searches (search statements A, B, C) were designed and their positive predictive value increased by using study type filters (search statement D). These searches were not restricted to the abstract or title fields.

  • ‡ The positive predictive value of the search strategies was increased by restricting search terms to the title field only, by using permutations of subject term combinations, or by using fewer search terms.