Current rapid social change and the highly complex health care environment indicate a need for nurses to develop good problem-solving skills (PSS) in complex situations  . In Japan, the complexity of many health issues and policies has led to a rise in specialized service departments, leading to new health-related demands for public health nurses (PHN) working in the community. Increasingly, more PHNs are obtaining work opportunities in unfamiliar areas of practice, meaning that they must also solve unfamiliar problems. PHNs―and indeed all nurses working in the community―must develop high-level PSS to deal with these unfamiliar problems. These skills need to be incorporated into nursing education and practiced to produce students with flexibility and competence in problem-solv- ing.
PSS are essential skills for nurses along with critical thinking  . Notably, “pro- blem-solving” and “critical thinking” are often used interchangeably   . Both are the focus of problem-based learning (PBL), a prominent student-cen- tered approach in nursing education   . In the present study, we focus on PSS using analogy, which may be an important means of solving particularly unfamiliar problems  . Analogy in problem solving refers to how people recognize similarities between a familiar problem (i.e., the base) and a relatively unfamiliar problem (i.e., the target), and apply the solution of the base to the target   . Analogy has been examined in a variety of fields and is recognized as a key concept of relational reasoning, which holds an increasingly important place in educational practice  .
PHNs must expend considerable time and effort to learn new PSS upon transferring departments. However, this does not necessarily mean that transferring requires PHNs to start from the beginning; indeed, PHNs can generally apply PSS acquired in previous departments. However, it has not been empirically demonstrated how PHNs apply such past PSS to new areas of practice, and whether PSS in the new areas can be developed using those learned in past areas. Identifying the characteristics of PSS using analogy in PHNs would help inform and improve nursing education strategies including PBL.
We apply the framework for analogy in this study to clarify how PHNs apply PSS from a particular area to new areas. In this study, we select the areas of mental and maternal health because of their inherent relationship: for instance, there is strong evidence that parents with mental health issues are more likely to abuse their children  . In Japan, the main areas of public health practice in which con- sultations are provided are as follows: maternal health, adult health, geriatric health, mental health, communicable diseases, intractable diseases, and handicapped persons. Recently, a new area in which consultations are provided―per- sons under social assistance―has emerged. Maternal health is the largest area for PHNs  . All of these areas are addressed by local government departments, with some governments having specific departments for each area and others having several areas covered by a single department.
1.1. Research Questions
We sought to answer two research questions. In a public health setting, how can mental health PSS be applied to maternal health PSS? Can maternal health PSS be developed using mental health PSS?
According to Holyoak & Thagard  , analogy in problem-solving comprises the following process: a problem-solver selects a base by retrieving information about it from memory (selection), after which they “map” the base to the target and generate inferences about that target (mapping); then, they adapt and evaluate these inferences to consider the unique aspects of the target (evaluation), and eventually learn something more general from the success or failure of the analogy (learning).
As noted in the above process, analogical thinking must begin with retrieval of an appropriate base from the massive storage of long-term memory  . Holyoak and Koh  posited that bases and targets possess two levels of similarity: surface and structural. Surface similarity refers to a resemblance between the objects in the base and target and their properties, whereas structural similarity is a resemblance between the underlying systems of relations in the base and target  . Generally, surface similarity is the main determinant of base access and facilitates retrieval  , while structural similarity influences mapping and is considered the defining feature of analogy  .
2.1. Design and Sample
This study employed the multiple case study design mentioned by Yin  . This type of case study inquiry benefits from prior development of theoretical propositions to guide data collection and analysis. The case unit of this study comprised three levels: the first level was the PHN, the second level the consultation, and the third level the PSS. The PSS were considered the main case unit because our aim was to study their applications via analogy. A case study format allowed us to use a combination of qualitative and quantitative data  . This study used the analogy process explicated by Holyoak & Thagard  as the framework.
We employed objective sampling in order to obtain PHNs who had specifically used analogy in problem-solving. Specifically, based on prior research related to analogy, we needed PHNs who had experience working in two different departments. Using analogy depends on temporal continuity  for accurate recall; therefore, the inclusion criteria were being a PHN who had transferred from a mental health department to a maternal health department within the past five years (because this would ensure that their memories of the former department were fresh) and who was still working in the maternal health department (to prevent contamination of memories). We included PHNs who had initially worked in the maternal health department as well as PHNs who had worked in maternal health department before working in mental health department, because we were also interested in whether maternal health PSS can be developed using mental health PSS.
2.2. Data Collection
In the Kanto area of Japan, 12 cities had both mental health and maternal health departments in their public health system. We contacted these 12 cities in January 2014 to identify currently working PHNs who met the inclusion criteria. Of these 12 cities, seven had PHNs who met the inclusion criteria. We sent research announcement documents to one or two potential candidates in each city; if the candidates were interested, they were contacted by the first author. One candidate declined participation because she could not talk about her consultations. Thus, eight PHNs working in six cities participated in the study.
A total of 8 participants in the sample had an average age of 42.9 (range 35 - 52) and all were female. Their average years of experiences as PHNs were 18.5 (range 11 - 27) and they transferred to the maternal health department within 1 - 4 years after the mental health department. Before transferring to their current maternal health department, five PHNs had previous experience working in maternal health departments and three PHNs did not.
We asked PHNs to talk about three or four consultations that they themselves had judged to involve application of mental health PSS to maternal health PSS. A consultation in terms of public health interventions is defined as the process of seeking “information and [generating] optional solutions to perceived problems or issues through interactive problem-solving with a community, system, family or individual”  .
The interviews were semi-structured, lasted for 90 - 120 minutes, and used an interview guide that followed the analogy process. The interview guide was pre- tested by two PHNs. They found that they could not speak in detail about their consultations because of how complex and long the consultations were, so the guide was modified to facilitate easier conversation. The guide consisted of the following: (1) a summary of situations involving a maternal health consultation (target) and a mental health consultation (base); (2) the similarities between the target and base, how they were connected, and whether participants had had previous similar consultations (selection); (3) how participants applied the base PSS to the target PSS (mapping); (4) whether the analogy was a success or a failure and why (evaluation); and (5) what participants learned from the analogy (learning). We asked PHNs about points (2) to (5) for each PSS used in a consultation. The structure of the analogy process in this study is shown in Figure 1.
Figure 1. Structure of the analogy process in this study.
2.3. Analytic Strategy
2.4. Quality Assurance of Results
Regarding construct validity, we asked interviewees to confirm case information by viewing their consultation reports. Case studies aim to expand and generalize theories (analytic generalization) rather than enumerate frequencies (statistical generalization)  . The sample size was enough to ensure that case findings overlapped, allowing better analytic generalization. One of the co-authors assisted with the discussion of findings by reviewing data and qualitative analysis. Regarding the reliability, two co-authors analyzed the same cases independently for two consultations. They read the transcribed data, identified the target and base PSS, and conducted the same analysis as the first author. After this analysis, they compared their results with each other and with those of the first author. In addition, all participants were asked for member checks and all agreed with the main results of this study.
2.5. Ethical Considerations
The summary and objectives of this study, voluntary basis of participation, confidentiality, and autonomy were explained to PHNs orally and in writing. Written consent was obtained before each interview. This study was approved by the Research Ethics Committee, the Faculty of Medicine, the University of Tokyo (January 8, 2014; No. 10358).
The analysis flow and main results are shown in Figure 2. Of the 8 PHNs (i.e., the first level of the case unit), five PHNs had previous experience working in maternal health departments before transferring to their current maternal health department, and three PHNs did not. Regarding the second level of the case unit, twenty-seven maternal health consultations were reported by the eight PHNs,
Figure 2. Flow of analysis and main results. PSS: problem-solving skill; PHN: public health nurse.
24 for child abuse prevention and three for childcare and child education. Finally, regarding the third level of the case unit, PHNs used 1 - 4 PSS with analogies per consultation. A total of 59 PSS with analogies were included as main case units for further analysis. We explained how PHNs applied the mental health PSS to maternal health PSS at each stage of the analogy process.
3.1. Selection Stage
The selection stage refers to how a PHN selects a PSS as a base by retrieving information about it from memory to solve a target current problem. We sought to understand how PHNs selected the base in terms of surface, structural, and decisive similarity, as well as the presence of particular consultations as a base.
Regarding surface similarity, we added a sub-item of psychiatric symptoms as an objective index of mental illness. A history of psychiatric treatment appeared in 13 consultations (28 PSS) and psychiatric symptoms in 15 consultations (38 PSS).
Regarding structural similarity, we created sub-items of “client reactions”, “cli- ent condition or situation” and “methods of support by PHNs”. Client reactions included 14 PSS and consisted of client verbal responses, facial expressions, and attitude to PHNs. Client condition or situation included 35 PSS and consisted of strange smells, clumsy, mother transferring from another area, a period of instability, self-accusation, and difficult childhood. The methods of support by PHNs included 13 PSS and consisted of step-by-step approaches, making changes to the current situation, and finding key people.
The decisive similarity in the base selection was a history of psychiatric treatment, with 2 of 27 PSS (7.4%); psychiatric symptoms, with 10 of 38 PSS (26.3%); client reactions, with 11 of 14 PSS (78.6%); client condition or situation, with 26 of 37 PSS (70.3%); and methods of support by PHNs, with 10 of 14 PSS (71.4%). We noted that structural similarities were likely to be decisive for selecting bases. Exemplars of structural similarity are shown in Table 1.
A mother was hospitalized with postnatal depression. I heard that she was highly impulsive. In the previous mental health department, I heard of a child whose arms were impulsively cut by the mother. I also heard that a criminal with mental disorders killed her own child. Although they were not my clients, I judged that the mother would be high risk if she was discharged (No. 40).
3.2. Mapping Stage
Table 1. Exemplars of structural similarity.
We found patterns of mapping specific to PHNs (signature patterns) in addition to standard patterns. The signature mapping patterns found were “preventive mapping,” “adjusted mapping from failure,” and “attitude mapping while supporting.” Preventive mapping was found in 20 PSS (33.8% of 59), and involved inferring about future changes from the client’s background (client situation and condition), thereby preventing health conditions, childrearing behavior, and living conditions from worsening. Adjusted mapping from failure was found in 11 PSS, nine of which overlapped with preventive mapping. This mapping pattern referred to a base PSS being judged as a failure by the PHN; then, through reflecting on this failure, the PHN adjusted the PSS. Adjusted PSS were often aimed at preventing future failures in a given situation or condition. Attitude mapping when supporting was found in three cases. This mapping pattern referred to a base PSS mapping onto a target that was not a concrete skill but rather an attitude. Exemplars are shown on Table 3.
3.3. Evaluation and Learning Stages
The evaluation stage refers to how a PHN evaluates whether the application of the base PSS to the target PSS was successful. After evaluation comes, the learning stage, wherein, the PHN learns something more general from the success or failure of the analogy. In the evaluation and learning stages, many PSS were judged as
Table 2. Exemplars of standard mapping.
Table 3. Exemplars of signature mapping for PHNs.
successful by PHNs, thereby confirming their PSS for that situation. However, PHNs judged five PSS as failures or as difficult to accurately judge. This led them to reconsider how they used and/or should use analogy for these five PSS and thereby gain a learning experience. An exemplar of a PSS evaluated as a failure was presented by one PHN:
A mother interrupted her treatment for schizophrenia and said to me that she was “cured.” Based on my experiences with other patients, I believed that the condition of such patients becomes worse without treatment. I tried to make her restart treatment. However, a psychiatrist recommended supporting the mother’s current condition because the psychiatrist thought that the mother suffered from borderline personality disorder, not schizophrenia. I regret that I reacted too strongly to a past diagnosis (No. 24).
We posed two research questions: how do PHNs apply past PSS to new areas of practices (i.e., can mental health PSS be applied to maternal health PSS), and can PSS be developed using the PSS learned in past areas (i.e., can maternal health PSS be developed using mental health PSS)?
4.1. Applying Past PSS to New Areas of Practice
All eight PHNs applied mental health PSS to maternal health PSS. We identified some characteristics regarding how to apply the PSS by analogy stage.
In the selection stage, PHNs were likely to select a base according to structural similarity, which included client reactions, client condition or situation, and me- thods of support by PHNs, even if surface similarity was available. This result is supported by previous findings  that surface similarity is most important for determining base retrieval, but in real-world conditions, structural similarity is used more frequently. This is perhaps because PHNs often do home visits and face-to-face interviews that then become training for them in assessing clients in the clients’ daily living environments.
Preventive mapping (or preventive analogy, hereafter) was found to be a signature analogy for PHNs. Preventive analogy is PHNs’ inferring a future change in a patient’s condition from their background situation and conditions, with the goal of preventing a worsening of the current situation. For instance, PHNs’ motivation in a child endangerment situation is in response to the ethical implications of that situation; in other words, PHNs might act to avoid negative consequences such as joint suicide or child neglect. Preventive perspectives are important for PHNs’ goals and activities and are included in key characteristic of practice of public health nursing  and the activities guidelines for Japanese PHNs  . While the finding that PHNs used preventive analogy is unsurprising, it was meaningful to confirm in a research capacity because it is important for PHNs and for educated novice students to acquire these skills during their nursing education.
4.2. Developing PSS Using the PSS Learned in Other Areas
Two findings supported that PSS can be developed using PSS learned in other areas. The first aspect concerned one of the signature analogies for PHNs, “analogy developed from failures and successes”. Many PSS of adjusted mapping from failure overlapped with preventive mapping, likely because PHNs learned from the failure of a mental health PSS and therefore adjusted the maternal health PSS accordingly in current new area, and used this adjusted PSS preventively in future cases. PHNs also reconsidered all maternal health PSS that they judged as unsuccessful. This might lead them to adjust this unsuccessful PSS and try it again in the future. PHNs’ process of using, reflecting on, learning from their skills, and then testing new skills is reminiscent of experiential learning theory  . PHNs developed their skills via continuous revision of analogies in practice. Professional development cannot be truly completed, and professional skill goes beyond current highest skill  . PHNs can develop their own skills beyond their current levels through learning from failures and successes. We proposed that this set of skills can be practiced and taught in continuing clinical education possibly through the use of case examples and PBL.
The second finding pertains to PHNs who had worked in maternal health departments before working in mental health departments. PHNs that had experience in a maternal health department also used analogies based on mental health PSS rather than falling back on their previously used maternal health PSS. In other words, existing maternal health PSS were improved using analogies of mental health PSS. Although PHNs had transferred to a department requiring specific skills, they could develop these skills through analogy.
4.3. Implications for Nursing Education
The findings in this study on PSS using analogy may contribute to the improvement of nursing education strategies including PBL to facilitate PSS and related critical thinking skills. We found that nurses have characteristics in applying PSS that may differ from those of other professionals. If such nurse-specific characteristics reflect what nurses learn from nursing educational programs, these programs may become more effective and practical. For instance, the finding that PHNs were more likely to select a base according to structural similarity such as clients’ reactions rather than surface similarity such as psychiatric symptoms, may be an important point in education. Problem examples in educational programs could include clients’ reactions and situations, as it would help nurses acquire more careful observation skills, which are necessary to identify structural similarity.
In terms of continuing education, sharing domain-specific PSS among nurses is important for overall skill development. Specifically, nurses can learn from the consultations and information of other nurses and apply these skills to their own consultations using analogy. Next, this study showed that transferring departments does not mean an interruption in skill development of nurses. If nurses who transfer departments understand this, they may become motivated to work harder, even if considerable time and effort are needed. Moreover, if nurses know their PSS can be applicable to their nursing in other departments, they may be more interested in making departmental moves, and anticipate and look for ways to use their knowledge and skill sets in new settings. Therefore, transferring departments for nurses could be viewed as a positive strategy for developing PSS and important to their career development.
Among medical doctors, computer-aided decision support systems have become popular in clinical settings  . One such system―fuzzy cognitive maps― can be used to help address the specific problems of mapping knowledge bases for medical diagnoses  , and is similar to PSS using analogy in the current study. Therefore, similar computer-aided support systems can be developed for use in public health nursing in the future. Given that our findings represent knowledge accumulated from experts, it is expected that they will be useful in the development of such systems.
4.4. Limitations and Future Research
This study had some limitations. First, because we used case studies, which aim to expand and generalize theories, we cannot generalize our results statistically. A quantitative study on this topic could overcome this limitation. Second, our results are limited to the domains of mental health and maternal health. Finally, we focused only on PSS in consultation, while PHNs use many different skills in practice. How analogy affects PHNs’ other skills must be studied in the future. Furthermore, more research regarding PSS using analogy is needed in other nursing departments in order to clarify the signature PSS for nurses that may contribute to the development of more effective nursing education programs.
We would like to thank the research participants. This work was supported by research grant from the Mitsubishi Foundation, 2013 (Program Grant Number 25313).
Conflicts of Interest
The authors have no conflicting interest to declare.
M. K. carried out the data collection and participated in study design, analysis, and manuscript preparation. T. S., A. T., S. N., and K. M. participated in study analysis and manuscript preparation. All authors read and approved the final manuscript.
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