ARTICLE IN PRESS International Journal of Nursing Studies 44 (2007) 1064–1070 www.elsevier.com/locate/ijnurstu The telephone interview is an effective method of data collection in clinical nursing research: A discussion paper Kimberly Musselwhite, Laura Cuff, Lisa McGregor, Kathryn M. King Faculty of Nursing and Department of Community Health Sciences, University of Calgary, 2500 University Drive, NW, Calgary, AB, Canada T2N 1N4 Received 31 January 2006; received in revised form 24 March 2006; accepted 20 May 2006 Abstract There are varying points of view regarding the advisability and utility of using the telephone to conduct research interviews. When undertaking the Women’s Recovery from Sternotomy Study, we found the telephone was an effective mechanism for data collection. Our aim is to identify the advantages and challenges of using the telephone as a mechanism for data collection in clinical nursing research. The potential beneﬁts associated with using telephone interviews as a mechanism of data collection include (a) using economic and human resources efﬁciently, (b) minimizing disadvantages associated with in-person interviewing, (c) developing positive relationships between researchers and participants, and (d) improving quality of data collection. The potential challenges to telephone interviewing include (a) maintaining participant involvement, (b) maintaining clear communication, (c) communicating with participants who offer extraneous information, (d) encountering participants with health concerns, and (e) communicating with a third party. Telephone interviewing can be an effective method of data collection when interviewers understand the potential beneﬁts as well as challenges. We offer solutions to the identiﬁed challenges and make pragmatic recommendations to enhance researcher success based on the current literature and our research practice. Supportive training for interviewers, effective communication between interviewers and with research participants, and standardized telephone follow-up procedures are needed to ensure successful telephone data collection. We have found our ‘Manual of Operations’ to be an effective tool that assists research assistants to meet the requirements for successful telephone interviewing. r 2006 Published by Elsevier Ltd. Keywords: Telephone interviewing; Clinical nursing research; Data collection What is already known about this topic? Conducting interviews by telephone can be an effective method of data collection in nursing research. There are a number of potential beneﬁts as well as challenges to telephone interviewing. What this paper adds A literature review that demonstrates challenges can be managed to optimize success in telephone interviewing for clinical research. Practical suggestions on managing the challenges of telephone interviewing to achieve a successful interview (with valid data). 1. Introduction Corresponding author. Tel.: +1 403 210 3953; fax: +1 403 210 3818. E-mail address: [email protected] (K.M. King). 0020-7489/$ - see front matter r 2006 Published by Elsevier Ltd. doi:10.1016/j.ijnurstu.2006.05.014 Using the telephone as a mechanism for data collection in health research has increased in recent ARTICLE IN PRESS K. Musselwhite et al. / International Journal of Nursing Studies 44 (2007) 1064–1070 years (Carr and Worth, 2001; Evans et al., 2004; deLeeuw and Hox, 2004). Historically, the majority of research examining the effectiveness of telephone interviewing has been focused on its use in market survey and census (i.e., epidemiologic) research. Indeed, market and epidemiologic survey research has been widely undertaken in North America and Europe (deLeeuw and Hox, 2004; Carr and Worth, 2001; Nathan, 2001). Though the telephone interview can be useful to collect quantitative and qualitative data (Burnard, 1994; Coderre et al., 2004; Sturges and Hanrahan, 2004), less critical analysis and research have been done examining its use in clinical nursing research (Carr and Worth, 2001; Worth and Tierney, 1993). There are particular issues associated with collecting data for clinical nursing research over the telephone. These include ongoing consent, interviewing people at a vulnerable time (i.e., when ill or needing special care), attending to clinical emergencies, and managing conﬁdentiality. Through the Women’s Recovery from Sternotomy (WREST) Study, we have recent experience conducting telephone interviews with 480 women who underwent cardiac surgery. The WREST Study was a multi-centre clinical trial designed to test the effect of women’s use of a special undergarment over a 12-week period poststernotomy (King et al., 2005). Informed consent was obtained and each participant inducted into the study pre-operatively. Data were collected in person while the participants remained hospitalized. Following discharge, WREST Study participants were then interviewed by telephone several times throughout their post-operative recovery. These interviews were conducted at regular intervals from the participant’s ﬁrst day home from hospital to 12 weeks following surgery. More recently, the study has been extended to include a 1-year followup telephone interview. On average, each participant engaged in eight interviews with a telephone research assistant (TRA). This experience of conducting telephone interviews with women recovering from cardiac surgery ultimately led to the development of a telephone interview manual to assist TRAs to adhere to a standard of practice for the WREST Study and subsequent telephone-based studies. In this article we will identify the advantages and challenges of using telephone interviews in clinical nursing research, offer our pragmatic solutions to these challenges, and make recommendations from both our practice in clinical trials research and from other authors experienced in this method of data collection. 2. Beneﬁts of conducting telephone interviews for data collection Telephone interviewing may be advantageous for both researchers and study participants. Here we share 1065 the beneﬁts identiﬁed by other authors as well as those found by the WREST Trial TRAs. 2.1. Using economic and human resources efficiently Cost-effectiveness is the most frequently identiﬁed beneﬁt of telephone interviewing (Bauman, 1993; Burnard, 1994; Corey and Freeman, 1990; Marcus and Crane, 1986; OSU Bureau for Social Research, 2004; Siemiatycki, 1979; Tausig and Freeman, 1988; Wilson and Edwards, 2002; Wilson et al., 1998). Using the telephone as a conduit to study participants is less expensive than requiring the participant or the research associate travel for an in-person meeting. Marcus and Crane claimed that relative to in-person surveys, using the telephone could reduce data collection costs by 50–75%. Use of the telephone allows interviewers to cover a greater geographic area (Burnard, 1994; Wilson and Edwards, 2002) in a timely fashion, rendering a more efﬁcient data collection process (Bauman, 1993; Burnard, 1994; OSU Bureau for Social Research, 2004). Moreover, when the participant is asked to travel to an interview location, expensive clinic space is often required. When the telephone is used, the costs of travel and potential lost time are forgone and convenience is greatly enhanced. This was particularly so when undertaking our multi-centre clinical trial (King et al., 2005). Interviews conducted by telephone may also be completed at a faster pace than those undertaken inperson (Wilson and Edwards, 2002; Worth and Tierney, 1993). The use of telephone interviews for the WREST Study allowed several centrally located and well-trained TRAs to speak with women from 10 centres across Canada, across four different time zones, at times which were convenient for them. We occasionally found that participants were not feeling well enough to participate in scheduled interviews, especially early in their recovery period. An advantage of telephone data collection is that a second call could readily be arranged. Alternatively, when participants were feeling better, they could use our toll-free number to return our call. Using this strategy and others identiﬁed here led to favourable response rates (489%) during the WREST Study. 2.2. Minimizing disadvantages associated with in-person interviewing The absence of face-to-face contact during a telephone interview can be advantageous to the research process. As necessary in our clinical trial, TRAs were expected to meticulously record participant responses on the data collection forms. Similar to Smith’s (2005) observations, we found that the WREST Study TRAs could take interview notes discreetly, without making the participants feel uncomfortable. Using the telephone for data collection interviews may also reduce some ARTICLE IN PRESS 1066 K. Musselwhite et al. / International Journal of Nursing Studies 44 (2007) 1064–1070 forms of response bias (i.e., through facial expressions or social desirability), as the interviewer and participant are potentially less affected by each other’s presence (Marcus and Crane, 1986). This, in turn, may increase the level of comfort for both parties and result in a more relaxed interview (Bauman, 1993; Smith, 2005; Tausig and Freeman, 1988). Also, the anonymity associated with telephone contact may enable participants to be more forthcoming with their responses (Sturges and Hanrahan, 2004). Researcher safety has also been cited as an advantage of using telephone interviews to collect data (Corey and Freeman, 1990; Evans et al., 2004; Marcus and Crane, 1986). Rather than having research assistants travel to locales where safety cannot be guaranteed, telephone contact may offer additional security. Nonetheless, over the course of a telephone-based survey conducted by Wilson et al. (1998) regarding continence care, several of the male study participants became ‘‘over familiar’’ (p. 319) with the female interviewers. To assure the safety of the WREST Study TRAs, interviews were conducted from a central research ofﬁce from which calls were blocked from any caller-identiﬁcation systems. A tollfree number was provided to participants in cases when they were unavailable at the time of the call. Also, TRAs were asked to reveal only their ﬁrst names to participants and others who may answer the telephone. 2.3. Developing positive relationships between researchers and participants Appropriate and beneﬁcial relationships can be built over the telephone with study participants. Interviews are more successful (i.e., valid and authentic responses are gleaned to interview questions) when a relationship is established (Carr and Worth, 2001; deLeeuw and Hox, 2004; Evans et al., 2004; Sturges and Hanrahan, 2004). Though WREST Study participants had developed a rapport with the on-site data collector, the initial telephone contact was particularly important. The ﬁrst phone call was the time at which participants formed an important ﬁrst impression of the follow-up (i.e., postdischarge) portion of the WREST Study that could ultimately affect their ongoing participation. Many women in the study stated they enjoyed the regular contact with TRAs and appreciated the opportunity to share elements of their surgical recovery. Other authors have described how study participants can beneﬁt from being able to talk about their experiences and concerns over the telephone (Worth and Tierney, 1993; Tausig and Freeman, 1988). 2.4. Improving quality of data collection Conducting telephone interviews from a central location can improve the quality of data collected, as it allows communication between multiple interviewers and enables greater supervision of TRAs by the investigators (Marcus and Crane, 1986; Wilson and Edwards, 2002). TRAs receive ongoing training and support, which has been cited as essential for perceived job success (Marcus and Crane, 1986; Wassink et al., 2004). Moreover, inter-rater reliability can be more readily determined, as is essential in any clinical trial. Finally, while undertaking telephone interviews to collect data is more time consuming than using mailed questionnaires, telephone interviews may reach a wider spectrum of the population as the respondents are not required to read or write (OSU Bureau for Social Research, 2004). As early as 1979, Siemiatycki concluded that the quality of the information obtained in telephone and in in-person interviews was comparable and the extra expense of home visits was not justiﬁed. Response rates for telephone interviews have been described as ‘moderate to high’ (OSU Bureau for Social Research, 2004) relative to other methods. 3. Challenges to conducting telephone interviews for data collection Upon our review of the relevant literature and our extensive experience, we became aware that there are potential challenges to telephone interviewing. Here we identify the challenges and our recommendations for practice. 3.1. Maintaining participant involvement As early as 1986, Marcus and Crane observed that telephone interviews may elicit a lower rate of cooperation as do in-person interviews. Some authors have noted that a rise in the number of unsolicited (or ‘cold’) calls received in today’s homes (Carr and Worth, 2001; Evans et al., 2004) may dissuade potential participants from agreeing to a telephone interview. Survey methodologists have studied introductions made over the telephone. They concluded that a ‘not selling anything’ introduction can be very useful in soliciting cooperation from those receiving an unsolicited phone call (deLeeuw and Hox, 2004). We contend that telephone interviews elicit similar and possibly higher response rates when well-established procedures that focus on consistent courtesy and respect for study participants are in place. In our experience with the WREST Study, no ‘cold calls’ were made; study participants were recruited inperson by trained research assistants who advised participants of the interview schedule. Smith (2005) claimed the two primary reasons for non-response to telephone interviews were that the participant had forgotten or that unforeseen events prevented them from being able to keep the appointment. We found that ARTICLE IN PRESS K. Musselwhite et al. / International Journal of Nursing Studies 44 (2007) 1064–1070 non-response to calls was usually the result of one of three situations: (a) participant activities conﬂicting with scheduled interviews, (b) participant confusion over study procedures, and (c) participants feeling too ill to engage in the call. An important acknowledgement in the WREST Study was that the participants could have limited recall of the study procedures that were initially presented to them during the hospitalization period. In any study, particularly in which participants are recruited during a stressful time, participants may be unclear about the duration of their participation and the number of data collection points. For example, some women in the WREST Study control group thought that they were removed from the study because they did not receive the experimental treatment. It was also crucial to emphasize to these participants that without control group input, sound experimental research would not be possible. As a matter of maintaining participant involvement and ethical procedures, TRAs reminded the participants of the study aims, the work of participating in the study (i.e., number of calls, amount of time, and nature of questions), and that study participation was voluntary, before beginning each interview. One successful strategy used in the WREST Study was to inform participants of all calling dates and allow them time to write the dates down for reference. We also ensured that the participant and/or family had the telephone number (toll-free) of the central research ofﬁce should they have questions or concerns about the study or wish to reschedule their ‘meeting’ with one of the TRAs. Early in the telephone WREST Study data collection process, the TRA also determined if the participant had a preferred calling time. For example, calls that were scheduled soon after hospital discharge often needed to be scheduled around rest periods or visits from homecare nurses. Thus, the participants’ preferred calling times often changed as the surgery recovery period progressed. All information regarding preferred calling times or calling date changes was conveyed to other TRAs. In any nationwide study, TRA knowledge of time zones and participant location is essential. A number of factors contribute to participant unavailability. In the WREST Study, these included rehospitalization, change of residence, return to employment, travel, as well as death. At the time of recruitment, we asked all study participants to identify an alternate contact person. Having this information helped us to ensure that participants and valuable data collection opportunities were not lost or that families of participants who died were not contacted needlessly. It is preferable that the alternate person is not someone currently residing in the home of the participant (i.e., spouse). If the participant has returned to hospital, e.g., the spouse is less likely to be available to provide this 1067 information. The WREST Study TRAs also learned to balance the need to contact study participants with the participants’ right to conﬁdentiality. When making contact with another family member or the alternate contact person, it is important to leave only the most relevant information with the individual taking the message (this also applied to leaving messages on voicemail) and to not enter into a dialogue about the participant or her study participation. 3.2. Maintaining clear communication Participants can be indecisive about providing responses to interview questions, particularly when engaging in telephone interviews. Clear and careful articulation during the telephone call can reduce much frustration and miscommunication. Older people and those who are ill are particularly vulnerable to not understanding when the interviewer speaks quickly, unclearly, or seems impatient. In our experience, careful TRA training regarding telephone communication was imperative. Slowly and clearly articulating and repeating the interview question, and allowing adequate time for participants to consider the question and respond were very helpful strategies for successful data collection. Participants with hearing difﬁculties or for whom English was not their ﬁrst language could have difﬁculty understanding some interview questions. TRA’s speech rate and tone were modiﬁed to the listener’s capacity to allow for maximum comprehension and make study participation as easy as possible. Unlike in-person interviews, multiple methods of communication cannot be used during telephone communication. Changes in body language and other visual cues that may indicate confusion, irritability, and so on, are lost when undertaking telephone interviews (Carr and Worth, 2001; Thomas and Purdon, 1994; OSU Bureau of Social Research, 2004). Wilson and Edwards (2002) recommended that researchers avoid the use of complicated (i.e., multiple ﬁxed-response questions) questions when undertaking telephone interviews. Wilson et al. (1998) also endeavoured to reduce interview confusion by requesting that participants bring a pen and paper to the telephone to write down potential responses (i.e., zero means none and 10 means worst possible). McCormick et al. (1993) included prompts within the questionnaires to remind interviewers to review the categories periodically throughout the interview. We found all of these strategies helpful. There may be situations where participants’ uncertainty appears to be a more global problem (i.e., they present as confused and are unable to provide any answers without prompting). In this instance, there may be a physiological (e.g., pain) or psychological (e.g., stress) basis. If the participant does not appear to be in distress or immediate danger (see below), an interviewer ARTICLE IN PRESS 1068 K. Musselwhite et al. / International Journal of Nursing Studies 44 (2007) 1064–1070 may simply need to terminate the interview and reschedule for a more appropriate time. 3.3. Communicating with participants who offer extraneous information Tausig and Freeman (1988) suggested that participants’ sensitivity to responding to intimate questions can be minimized once a supportive relationship has been built between the interviewer and the study participant. As indicated earlier, relationship building with participants was an integral part of conducting successful interviews in the WREST Study. However, as other authors have noted, the existence of a supportive relationship may sometimes lead to another difﬁculty: the amount of extraneous material offered by the participant (Worth and Tierney, 1993). Some study participants are easily engaged and may have difﬁculty restricting their responses to the interview questions; thus, limiting timely completion of the interview. Howard et al. (1988) found that it was sometimes difﬁcult to complete the interview in the desired time frame with participants who liked to discuss their feelings and problems. The researchers attempted to resolve this problem by asking the study participants to refrain from discussing other personal matters until the end of the interview. In such a situation, we found the best approach was to politely and consistently redirect the participant to the interview question. 3.4. Encountering participants with health concerns When calling participants for health research, the nature of the study questions may elicit participants’ inquiry about speciﬁc health issues. In some circumstances, WREST Study TRAs were asked to advise participants about their health conditions and concerns. The focus of the participants’ questions was usually on general normal post-surgery recovery. WREST Study participants, e.g., often asked if other people also suffer from discomforts following sternotomy. The policy, as written in our ‘Manual of Operations’ was that TRAs were not to provide medical advice to study participants. However, when participants were seeking reassurance that their symptom was not unique, the TRA could make a general statement such as ‘difﬁculty sleeping is not uncommon in people who have had heart surgery’. In some cases, participants had a serious medical concern that warranted an appointment with their healthcare provider. Much more infrequently, TRAs could encounter a participant who presented in a condition that required emergency care. TRAs in health research should be aware of symptoms of serious and urgent medical concerns that are relevant to the participants with whom they will speak. An algorithm of care was created for the WREST Study TRAs to enable them to determine if the participants’ presenting symptoms were of a non-urgent or urgent nature. In one arm of the algorithm, the participant was referred to her healthcare provider. In more urgent situations, the participant was strongly encouraged to contact a relative or friend immediately for help or call emergency services. If the participant was unable to make the call, the TRA could do so with the participant’s permission. Thereafter, TRAs made contact with the participant or named alternate contact, to assure that care had been obtained. To assist in documentation and follow-up of these situations, the WREST Study research team created a Recommendation for Urgent Care Form. The form enhanced communication between TRAs. It also acted as a quality assurance measure to ensure consistent and appropriate care of study participants. 3.5. Communicating with a third party Family members can be vigilant in protecting a study participant from perceived intrusion and attempt to block contact. During the WREST Study, we occasionally encountered this difﬁculty. Sometimes, the vigilant family member was unaware of the participant’s involvement in the study or was concerned that the participant would ﬁnd the interviews tiring. When this occurred, it was important to maintain the participant’s privacy, reminding the family member that the participant had been informed of, and consented to, receiving calls from our ofﬁce. The toll-free number was then left for the participant to return our call, or we arranged to call again at a more appropriate time. In cases when a family member persisted in rejecting our contact with the participant, we would politely but ﬁrmly indicate that as informed consent was obtained from the participant, the decision to terminate study participation must, when at all possible, be her decision. We would conclude the conversation indicating the date of the next scheduled interview. With careful and respectful perseverance, access to the participant was often achieved. This situation however, brought to light the importance of having family members present at the time of consent or made aware of a participant’s consenting to study participation. In summary, challenges arise when conducting telephone interviews. We have offered recommendations for researchers and interviewers to enhance the success of using telephone interviews as a data collection method. We have identiﬁed additional suggestions for successful telephone interviews in Table 1. 4. Communication in research and the manual of operations Communication between TRAs is essential for effective data collection. Over the course of the WREST ARTICLE IN PRESS K. Musselwhite et al. / International Journal of Nursing Studies 44 (2007) 1064–1070 1069 Table 1 Additional recommendations for conducting telephone interviews Listen to another interviewer using study questionnaires, then practise the interview process to effectively prepare for the telephone contact. Arrange the research space in advance to ensure ease of accessibility to research tools and relevant notes, as well as privacy during the interview (Smith, 2005). Whenever possible, try to conduct interviews when participants can access a landline for cost, privacy, and safety reasons (Kuusela and Simpanen, n.d.). Ensure that it is a convenient time for both the interviewer and the participant before initiating the interview (Burnard, 1994; Smith, 2005; Wilson and Edwards, 2002). Do not start an interview without being sure there is enough time for completion. A participant should not feel pressurized to quickly provide answers for the convenience of the interviewer. Conﬁrm that you are speaking with the correct person before commencing the interview—one family member in our study went so far as to impersonate the participant. Set the participant at ease by reviewing the aims of the interview (Burnard, 1994; Smith, 2005), reassuring the participants of their anonymity (Wilson and Edwards, 2002), then begin the interview with more readily answered generic questions (Burnard, 1994). Humour can be an effective tool when used appropriately. If taking notes during the interview, inform the participant so they may be prepared for pauses during the conversation (Smith, 2005). Always thank the participant for their time and assistance (Wilson and Edwards, 2002). Write any additional notes immediately following the interview (Smith, 2005). Each page of written records should contain a participant identiﬁer. Paper can stack up quickly and there is potential for pieces to be misplaced. Study, ﬁve TRAs undertook interviews with women following sternotomy. Thus, communication about how the participants wished to be addressed, their preferred calling times, as well as any potential concerns or challenges were imperative. We have created a ‘Call Report Form’ to accompany each participant’s ﬁle on which important notes were written for the next interviewer. We also implemented the use of a communication book for general information to be shared amongst the team. These standardized mechanisms for communication were invaluable to us. Finally, comprehensive training or operational manuals are essential to the success of telephone interviews and can enhance the interviewers’ feelings of support (McCormick et al., 1993) and preparedness (Wassink et al. 2004). Our ‘Manual of Operations’ was one of the most important tools created in our research ofﬁce. As a result of our experiences during more than 2 years of telephone interviewing for the WREST Study (and others), this manual has been revised on a regular basis. This manual was produced to assist new interviewers to effectively collect data over the telephone. It contains information about and expectations for telephone etiquette, dealing with challenging situations, conducting a telephone interview with a participant, and guidance for completing the various forms associated with each of the studies managed from our ofﬁce. The manual has a general focus on telephone interviewing and includes appendices pertaining to speciﬁc elements from each study managed through our ofﬁce. It has been an effective tool in training our research assistants who engage in telephone interviews, offers a foundation for establishing consistency in interviews (including intraand inter-rater reliability), and serves as the basis for ongoing feedback and evaluation of research assistants associated with our ofﬁce. 5. Conclusion Telephone interviewing is an effective method of data collection for clinical nursing research (quantitative and qualitative) when interviewers are properly prepared. Market survey and epidemiologic research has been widely undertaken by telephone. However, undertaking clinical nursing research by telephone mandates that particular issues be addressed (i.e., ongoing consent, interviewing people when ill or needing special care, attending to clinical emergencies, and managing conﬁdentiality). In this article, we have described potential beneﬁts and challenges as well as proposed solutions associated with undertaking telephone interviews. We have also provided examples and recommendations from the literature and from our own experience to assist researchers considering using the telephone interview as a mechanism of data collection for their own clinical studies. In sum, using a combination of effective communication and standardized procedures is essential to the success of data collection by telephone. Speciﬁcally, when undertaking multi-centre trial research, we found the telephone interview was an efﬁcient, reliable, and valid form of data collection. Moreover, when ARTICLE IN PRESS 1070 K. Musselwhite et al. / International Journal of Nursing Studies 44 (2007) 1064–1070 participants have a good research experience, they may be more open to participating in future studies. References Bauman, L.J., 1993. Collecting data by telephone interviewing. 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