Vignette technique is used as an elicitation tool which facilitates the discovery of subjects’ responses to presumptive situations (1). Text forms of vignettes are usually used by the researchers (1, 2); nevertheless, other forms, such as static and moving images (film) (2) video material and cartoons (3, 4) and other forms of presentation have been also employed (2, 5, 6). The textual vignettes range from short written texts to long story prompts (2).

   Vignettes are defined as “short stories about hypothetical characters in specified circumstances, and the interviewee is invited to respond to those situations” (Finch, 1987) (7).

Other descriptions of vignettes included: any short scenarios in the textual or pictographic form regarding stimulation responses to distinct scenarios(8); the actual cases of people and their behaviors in which participants can propose their statement or viewpoint(9); and a tool for the extraction of important points from stories about characters, opinions, beliefs, and attitudes(10).-Forrester (1990) has described vignettes as “ the simulations of real events: asmall illustration “ in research terms(11). Apart from the written form, the media of vignettes include videotape, computer-based data, and music (12).

   In clinical research, vignettes have been broadly used in recent decades to compare the quality of clinical care. Moreover, it has been applied to assess various practices in health care systems, specialties, or clinicians, such as conducting vignette-based research to identify disparities in practice. For instance, it can be used to assess the management of postpartum hemorrhage among midwifery students (13, 14). In addition, vignettes can also be employed when it comes to revealing discrepancies between available guidelines and practices and assess the quality of care provided by health care workers in such fields as midwifery or obstetrics (13, 15-17).

   Vignettes have been used in quantitative (18) and qualitative research, and the use of vignettes in qualitative research is on the rise (19). It is worthy to note that in qualitative research, vignettes are more convenient, especially in well-designed qualitative research (20).

   Researchers are nowadays investigating this issue, and more studies have been recommended for the exploration of its different aspects (2-4). The authors of this paper, during their research project, have been diagnosed that vignette technique can be used as a very valuable and useful tool for data collection in their ethno phenomenological study; nevertheless, they could not find adequate information in this regard so that decided to conduct this narrative review. The present study therefore aimed to provide comprehensive and thorough information about vignette technique through a narrative review.

Materials and Methods

   This was a narrative review which was performed using some keywords, including “vignettes”, “qualitative research”, and “quantitative research”. The following databases were searched: ISI Web of Science (65), PubMed (27), Scopus (24), CINAHL (110), ProQuest (23), ERIC (44) as well as Science Direct (123), since their inception up to September 5^th, 2018 to assess those studies regarding different aspect of vignettes. No language restrictions were imposed.  A number of 303 records were excluded on the basis of title and abstract and 105 books and articles were reviewed to obtain information concerning the various aspects of vignettes and their applicability in qualitative and qualitative research in different disciplines.

To meet ethical considerations, the authors just reviewed and collected related publications.  

Results

   In the current paper, the thorough research regarding vignettes has been expressed as execution of vignettes, practical reward of vignettes, limitations of the vignettes, and building vignettes. The results and important practical aspects of these issues are represented in the following sections:

Execution of vignettes

   The administration of vignettes varies according to the design of the research and the way of data collection, vignettes presentation, and how to gain the responses (12).

   Data collection: Vignettes have been used to extract the opinions of participants either in a group or individually. They are of great help to members in expressing their opinions in a group and discuss with each other (5, 21). Moreover, they provide an opportunity to compare the interpretations of different groups regarding the equal situation and express their values and norms of behavior (22).

    Presentation of vignettes: Vignettes can be presented in a myriad of ways. Open-ended questions have been demonstrated to be of great value (2, 10, 23, 24), and another popular technique is unfinished sentences to provoke discussion among participants (25).

   Open-ended questions could promote creativity among people (24). They can also provide more realistic responses to real-life conditions (26). On the other hand, closed or forced-choice vignettes (27) tend to be used more frequently in quantitative research. They allow a broad kind of variables to be integrated in the research design (1, 12, 28-31). However, they are not as useful as the open-ended questions for the social situations (1, 2).

   In theory, employing a mixture of closed-ended and open-ended questions capture the benefits of both; nonetheless, such an approach may be inappropriate or impossible (1, 2, 7, 12, 32, 33). Therefore, it has been recommended that the use of closed or open-ended questions be systematically evaluated due to the dearth of information in this regard (2, 34).

    Response perspectives:Participants may   respond to vignettes differently: (1) from the point of the vignette characters; (2) people more commonly (3) and participants own personal opinions (2, 12, 35) depending on the aim of the research, topics, and participants of the group (2).

   In some studies, the researcher asks the participant to adopt the role of an informant, then poses his/her questions in terms of the character and condition of the vignettes (34, 36-38). In some other studies, participants regard themselves as the vignette character and then respond (39-41). It is noteworthy that in vignettes in which participants act as consultants, they can respond from the viewpoints of vignette characters or may discuss with them regarding the probable reaction of peers and other people to vignette situations (42-44).

   In qualitative research, participants are commonly asked to respond to a particular situation by stating what they would do, or how a third person, generally a character in the story, would react to certain situations or occurrences, which often entail some form of moral dilemmas. Sometimes participants are asked to comment on both (45).

   In summary, vignettes in qualitative research could be administered as an ice breaker, eliciting cultural norms derived from respondents’ attitudes and beliefs about a specific situation, as a complementary technique alongside other data collection methods, in exploring potentially sensitive topics, examining different groups’ interpretations of a ‘uniform’ situation, closing the interview, and within a focus group (7, 9, 10, 12, 45-49).

Practical reward and strength of vignettes

   Vignettes are definitely of great help in difficult or sensitive topics by the desensitization of subject matter (1, 5, 35) and directing attention to specific elements of complex processes (12), and this matter has been well documented (5, 7, 10, 25). Therefore, the participants feel more comfortable and less threatened to speak about their own situation, real opinions, and actions since they feel it is non-personal (1, 2, 5, 7, 12, 22, 25, 33, 35, 50, 51).

   This method has been used for data collection when the researcher has no other way to collect the data at all or for a few cases, as well as when there are methodological challenges (5).

Vignettes sometimes lead to an ambiguity in the results helping the researcher to find new opinions and situations which were not previously distinguished. Therefore, flexibility is regarded as one of the important elements of a vignette (52).

   In research studies, the manifestation of diseases can be written in the form of vignettes (as a short-term description), which illuminates how the signs and symptoms of diseases manifest themselves. These descriptions which are known as clinical vignettes may be used as effective tools to measure a variety of variables regarding the nature of disease and also the performance of health care workers in different aspects (53).

   It has been well documented that vignette technique is a valuable method for collecting less socially desirable data since participants assume a role in the vignettes (1, 2, 5, 41, 54). In addition, a phenomenon known as Hawthorne has been argued by Gould (1996) as one of the main opinions in using them (55). He noted that the growing acceptance of vignettes is due to the increasing recognition of the boundaries of questionnaires in studies of attitudes, perceptions, beliefs, and norms (55). Discussion during individual interviews (10) and stimulation for group discussions can be mentioned as other advantages of the vignettes (56). Furthermore, this method is economical owing to financing, time of research, and collecting more uniform data (55).

   In addition, using vignettes, multifaceted issues could be assessed (57), and a distance would be created between the participants and the researcher (5, 25, 50). Moreover, due to the lack of detail in a vignette, participants fill the gap through their responses, which is important for demonstrating that the interpretation of participants is valuable as a research tool (52).

   When we use the vignette method, the participants’ awareness of subject matter mandatory (58), rather we can use it to stimulate is not participants' meanings, automatically (59, 60). In these studies, an unrealistic event could also be used to assess peoples’ reactions (5). Vignettes can be employed when it comes to difficult access to participants and serious ethical problems (1, 5).

  In qualitative research, vignettes can be used as an ice breaker and a way for rapport development, enhancement of existing data, or generation of those data which has not collected through other methods, such as interviews or observation. Moreover, it desensitizes sensitive morally-charged topics, stimulates cultural norms resultant from attitudes and beliefs of participants regarding a specific situation, and discloses harmony or disharmony in the incongruent group regarding uniform condition

(7, 9, 10, 12, 45-49). The vignettes can be used as an efficient tool for theoretical sampling when the grounded approach has been used (1). In a study conducted by Fook et al. (1997), new vignettes were utilized for probing emergent themes as the research developed (61).

Limitations of vignettes

   Validity could be mentioned as one of the biggest methodological concerns when vignettes are used in quantitative research (62). Although vignettes stimulate the elements of research in varying grades (55, 63), they are unable to fully capture the elements of reality and the lives of people the same as other research tools (2, 5, 64-66).

   In fact, despite the advantages of vignettes, there is still debate surrounding their ability to represent social realities (10, 25). However, some researchers found that vignettes are efficient when it comes to the schematic nature of presenting the material. Therefore, it is necessary to access the consistency between the used vignettes and the actual life situations (64, 67). In this regard, written vignettes (paper people vignettes) are not recommended, as compared to videotaped or real-life events since they could shed more light on situation or behavior of people (64, 67).

   The detachment of participants' experience from vignette characters is another important issue which needs consideration (68). If this gap is very huge, the participant will face serious problems while adopting the role of vignette characters (68) (2) (5). Interpretation is another issue which is not fully understood in the use of vignettes (7, 58, 69). Finch (1987) reported that the dearth of information, the way of obtaining information in vignettes, kinds of assumptions participants should make during interpretation, and specific elements of vignettes lead to certain responses (7). It is worth noting that these issues can be addressed using less structured vignettes; consequently, disclosure and clarification of the subject under the study could be attained (2).

   Another issue worth mentioning is the debate surrounding the relationship between belief and action (2) which causes serious concern over capturing reality in the development of vignettes (12). It has been indicated that there might be a disparity between what people think they would do in a given situation and their actual behavior (22, 25, 27, 51). Nonetheless, Finch (1987) suggested that this inconsistency is not a matter of concern (7). In general, the complex relationship between the reported behaviors and the actual ones is under question (1).

Building vignettes

   Different factors contribute to the construction of vignettes, and the aim of the study plays the leading role in this regard (22, 57); nevertheless, some other key factors may also exist in different projects. It is recommended that four issues be considered for the development of vignettes, including data sources, vignette format, capturing reality, and vignette/participant congruence (12).

   However, their appropriateness for the research topic, participant type and their interests, relevance, realism, and timing of vignettes in the research are of paramount importance during the development and construction of vignettes (2). These items are elaborated below:

    Internal validity of vignettes:The internal validity refers to the extent that the research topic under the study has been captured by the content of vignettes (55, 62). Different kinds of sources could be used for the construction of a vignette (12), including previous research findings, literature reviews, or a mixture of them (69-72), individual experiences of researchers and their consultants (34, 73-75) along with real case studies and personal experiences (33, 37, 43, 72, 74) . In general, if vignettes are employed in an appropriate manner, such studies will be considered ‘‘hybrid’’ research indicating the use of vignette increases the internal and external validity of the study (76).

   More specific questions should be asked to ensure internal validity, for instance, if the researcher has reviewed the related literature about vignette development? If an expert panel with adequate knowledge and experience for the judgment of vignettes appropriateness has examined them? If the vignette questions have been pretested for the extraction of vague or unsuitable items? (2)

   Generally, vignettes are piloted before their usage, and experts may be employed to evaluate their representation of the subject under the study (62). These arguments regarding vignette are worth assessment (1) and could reinforce this aspect of vignettes, especially in the studies which need more realistic vignettes (55, 62). Nonetheless, it is significant to consider the logic behind using vignette when it comes to internal validity (1, 32, 77-79)

    The topic of the research:The topic of the research should be taken into account for the construction of vignettes (2, 5). The textual form of the vignettes are commonly used; however, moving or static images, as well as the real actions of participants, can be employed (2). Textual vignettes could range from short written texts to longer stories; nonetheless, the distinguishing feature of vignettes is their conciseness (22, 51, 57). On the other hand, video vignettes provide more precise information with higher complexity, and they convey their meaning to participants more conveniently (2, 51). In this regard, in designing vignettes, it should be considered that video vignettes have higher cognitive demands, as compared to textual form (2, 64).

    The character of participant groups: The type of vignettes and the participant group should be matched (68). It should be considered that the type of vignettes and their character should be appropriate for specific individuals in the study (5, 12). As mentioned earlier, there is a range of different types of vignettes, such as narrative story, computer-based, music videos, or comic book style, flipbook, posters, response cards, games, and filmed materials (21, 25, 80, 81). For example, it could be frustrating if a young person is asked to imagine themselves as an elderly character (12). Therefore, some decisions should be made, such as checking the complexity versus simplicity, vagueness versus clarity, and informal versus formal language. In addition, vignettes must not be too complex to be easily understood (45, 51).

   To decide on the degree of vignette complexity, participant type should be taken into account (12). For instance, if participants are children or people with learning difficulties, vignettes should be designed in simpler forms (5, 25). When the textual form is less acceptable, we use image type of the vignette; nonetheless, the textual type may work well for other groups (2).

   Furthermore, the length of the vignettes seems to be important in working with specific groups of respondents (82). For instance, a 200-300-word text is suitable for young people and a 150-word text suits children (25). In people with learning difficulties, vignettes should be provided in small sentences and single words (5, 12).

These issues highlighted the importance of close attention to Vignette type (2, 12). Chambers and Craig (1998) suggested that more studies should be performed to assess the reliability and validity of vignettes, rather than developing new types (83).

    Notification, relevancy, realism, and timing: Vignettes are more effective when they seem real, are related to people’s lives and match participants’ interests (2). However, they are somewhat hypothetical depending on their construction, including realistic, fictional, or mixture of them (57). It is worth noting that more close attention is needed while constructing a vignette which is solely based on fiction (12).

   Lazenbatt and Wallace (2010) are of the belief that hypothetical vignettes are imperfect in their ability to capture real-life dynamics of decision-making processes (84). Other researchers suggested that if situations are in a hypothetical form, participants may answer in a similarly hypothetical manner (2). It is argued that less hypothetical vignettes are more likely to elicit actions which match the actual behavior (12). It should also be considered that unrealistic scenarios can make participants react negatively (52).

   Staging vignette scenarios (56, 85, 86), extensive written narratives, and storybooks (4, 10, 33, 87) would be of great help in maintaining participants interested. To avoid respondent fatigue, short vignettes employed at different times during research meetings, changing tasks, and offering breaks could be worthwhile (88). Moreover, a higher response rate can be obtained using such a vignette in the form of postal questionnaires (89).

   It should be mentioned that participants may lose their interest and get tired of responding, often repetitively, to a number of short vignettes. Furthermore, answering to vignettes repetitively can bring about a carryover effect from one vignette to another (90). This effect is more obvious when there is a slight continuity between the scenarios of the vignettes. In a similar vein, longer vignettes may be replied carelessly when the interest of participants declines over time (79).

   The timing of vignettes is also of utmost importance. The restriction of participants’ allocated time may distress the quality of data (91). In addition, Stolte (1994) disclosed that obligatory time limitations for answering vignettes lessen the effect of the vignette (92). Nevertheless, for the visual imagery vignettes, time is not as important as it is for textual or other forms since participants can answer them more quickly (59). However, the selectivity of vignettes is regarded as one of the valuable features of the method (2).

   In conclusion, it should be considered that vignettes need to be straightforward (51), and the phrasing of the vignettes should be considered (25). The language of vignettes should match participants’ literary skills, as well as such backgrounds as age, gender, education, and social class (82). Finch (1987) revealed that participants may assume that there are ‘correct’ answers. Therefore, it is important to assure them that there is no right or wrong answer when responding to vignettes (2, 7). The requirement of vignettes is adequate contextual information to enable the participants to distinguish the situation; nonetheless, it should be vague enough for participants to afford supplementary comments (45, 51).

Discussion

 Vignette technique is a method which has been applied in many disciplines over the past 50 years (12). It has a long history in exploring an insightful number of phenomena in behavioral, social, and health sciences in the form of quantitative or qualitative research (76).

   In the early 1950s, vignettes were used in anthropology and psychology; moreover, it has recently found its place in nursing (93) (94) (95). In addition, it is nowadays employed in disciplines such as education (81, 96), occupational therapy (27), social work (97-100), and nursing (5, 19, 55, 101-103). Furthermore, it is utilized for potentially sensitive social and health issues, such as sexual health, HIV, mental health, stigmatization, violence, as well as in specific vulnerable populations, such as children (10, 22, 25, 35).

   Torres (2009) pointed to the particular strength of vignettes when working cross-culturally since they allow researchers to take advantage of the ‘peculiarities’ of different cultures (82). Vignette studies can be used as a practicable alternative to other data collection tools, such as an interview or focus group. In this regard, vignette technique has been suggested to be a sensitive and ethical data collection instrument in research projects (14, 20). In this method, participants are able to focus on imaginary characters provided by vignettes; accordingly, the morally-charged and sensitive conversations could be initiated (14).

   In the studies which use vignettes, the researcher should ascertain that the prepared vignettes are congruent with the purpose of the study. More accurate vignettes (as a data collection tool) which match the aim of the study elicit more and deeper discussion among the participants (14, 20, 76).

The strength of vignettes lies in the fact that it could be used effectively in complex studies, highlights or unravels those subject matters which cannot be revealed during the common research process and for sensitive issues.