Research status and hotspots of economic evaluation in nursing by co-word clustering analysis

PubMed was the most popular and widely used database, comprising more than 28 million citations for biomedical literature from MEDLINE, life science journals, and online books. Medical Subject Heading (MeSH) term was a controlled vocabulary to index articles in MEDLINE.7 They were assigned to each document not only based on the abstract and/or the title but also based on the context of the whole document; thus, they contain high-density information from the document.8 “Cost–Benefit Analysis” was first introduced as a MeSH term in 1976. Any papers included terms, such as “Cost Utility Analysis,” “Economic Evaluation,” and “Cost Effectiveness Analysis,” could also be found using “Cost–Benefit Analysis.” We did not use other terms like “economic” or “cost” because their results included some studies that just simply calculate the healthcare cost instead of applying EE methods. Therefore, “Cost–Benefit Analysis” was searched as a MeSH term in PubMed up to May 2, 2018. We also used the function of filter to limit the journal category in nursing. All papers we found were included.

The data of title, author, country, language, year, and MeSH terms of the searching papers were exported in XML format. The XML file was processed in Bicomb 2.0,9 which is a text mining system to investigate the co-occurrence of bibliographic data in literature. The frequencies of title, author, country, language, year, and MeSH terms were accumulated and the connections between each paper were investigated through their MeSH terms. Statistical data were recorded in the system window and could be exported to Excel. To make the results more focused, the following words were combined or transformed, as they have hierarchical relationship based on MeSH Tree Structure. First, “Hospital Costs” and “Drug Cost” were merged into “Health Care Costs.” Second, “Health Promotion” was merged into “Health Education.” Third, “Education, Nursing, Associate,” “Education, Nursing, Baccalaureate,” “Education, Nursing, Continuing,” “Education, Nursing, Diploma Programs,” and “Education, Nursing, Graduate” were all merged into “Education, Nursing.” We also delete “Cost–Benefit Analysis” which is a search term that without reflecting any research topics. Demarcation of high- and low-frequency terms was calculated using the formula10: T=−<!-- − -->1+1+8⋆<!-- ⋆ -->/1/2, $\text{T}=\left( -1+\sqrt{{1+{8}^{\star }}\text{/}1} \right)\text{/}2,$where I1 represents the amount of terms whose frequency was 1.

Co-word matrix of high-frequency terms was produced by Bicomb 2.0. Hierarchical cluster analysis in SPSS 19.0 was used to analyze these data. Cluster method chose “Between-group linkage” and measure chose “binary: Ochiai” to generate Dendrogram.

We found 3,020 articles and they were published from 28 different countries, 91% of them from United States (1,973), England (722), and Canada (53). A total of 368 nursing journals were discovered. The top three were Nursing Economic and The Journal of Nursing Administration with 111 published papers and Infection Control and Hospital Epidemiology with 100. In total, 10,573 MeSH terms were detected in all the papers but 1,909 MeSH major topics were used to produce the highfrequency terms. The threshold value was 41 based on the formula calculation. Therefore, 42 high-frequency terms were obtained, accounting for 29.7% of the total (Table 1). The term “Education, Nursing” has the highest frequency of 185 and the second is “Nursing Staff, Hospital” of 182.

Dendrogram is shown in Figure 1. Based on the structure of dendrogram and professional knowledge, seven clusters representing seven research topics were classified and named. Details of each topic name and its

Figure 1

terms are shown in Table 2. The smallest group contains three terms and the largest group has 11 terms.

Hospital-acquired skin breakdown usually caused high economic burden on healthcare system.11 EE is helpful to discover much cost-effective nursing interventions in skin administration. Hotspots of this class of study focused on the comparison of different intervention and products to prevent pressure ulcers or fasten wound healing. For example, a study showed that nutritional support was cost saving and gained 0.005 quality-adjusted life years compared with standard care to prevent pressure ulcers.12 Another study found that a novel soluble beta-glucan gel has a shorter healing time that leads to cost saving over an annual budget cycle of £503 per patient, compared with methylcellulose dressing.13 With a deep understanding of the mechanism of wounds and the discovery of innovative products or equipment, this study will continue.

Three terms, “cross infection,” “infection control,” and “mass screening,” in this group indicate that the search topic is about infection prevention. Healthcare-associated infections (HAIs) are infections that patients get while receiving treatment for medical or surgical conditions. It is estimated that HAI led to costs of more than $100 million in one state of United States in 2009.14 In a study, seven strategies were found to be available to standard precautions in ICU, but based on the method of EE, the author found universal decolonization was the best choice because it was least expensive but moderately effective.15 Mass screening is a way for infection prevention. However, by EE, a study showed us that even though a universal methicillin-resistant Staphylococcus aureus (MRSA) screening may provide potential benefit in preventing MRSA infection, it is relatively costly and may be economically burdensome for a hospital.16

According to the MeSH terms definition in PubMed, “Health Education” means education that increases the awareness and favorably influences the attitudes and knowledge relating to the improvement of health on a personal or community basis; “Occupational Health Services” means health services for employees, usually provided by the employer at the place of work; and “Patient Education as Topic” means the teaching or training of patients concerning their own health needs. They all conveyed the topic of education on both health person and patient. People with chronic disease and employee in hospital or other place are main study participants. The cost-effectiveness ratios and cost per quality-adjusted life year were commonly used as evaluation indicators. Cost–benefit analysis supports the more widespread implementation of some education program,17 and also justify some programs are not cost-effective which should be further developed and modified.18

The terms in this study group include “Education, Nursing” and “Nursing Staff, Hospital” which rank top two of all key terms, indicating nursing education and management is the most popular research topic in EE. Nursing staff education and training is determined by management department of hospital, so these two kinds of studies would have strong connections. Improving the educational level of nurse means hospital has to pay more salaries for them, but unknowing whether the outcome can overweigh its cost. Therefore, this group of studies was to detect the economic value of nursing education. On the one hand, evidence added by empirical study, they have found increasing the baccalaureate nurses’ (BSN) dose to 80% for every patient could potentially result in $5.6 million in savings annually that would more than offset annual costs of about $1.8 million in increased salaries associated with BSN qualifications.19 On the other hand, management department tries to detect more efficient way to quantify the value that nursing professional development brings to the organization20 and explored more undiscovered resource to assist nurses. For example, they found providing training curricula to non-nursing staff to provide feeding assistance for nutritionally at-risk nursing home (NH) residents is cost-effective and has a positive effect on residents’ between-meal intake.21

Classifying this group of studies is difficult because it included the terms, such as “health care,” “Quality Assurance, Health Care,” and “Nursing Care,” which lack specific content. But we can think that the goal of EE is to improve the quality of health care. Therefore, we defined this topic according to the terms “nursing research” and “state medicine.” Mark advocated using cost-effectiveness analysis for nursing research and believed the information provided by CEA will be an important additional component of the evidence produced by nursing research.22 Wendy systematically reviewed papers about EEs in nursing-relevant research performed in the United States between 1997 and 2015. She found that evaluation indicators in these studies are not standardized and EEs have not been fully utilized in US nursing-related studies over the past two decades.23 Studies in this group gave us the importance of EE in nursing research and we should correctly use economic analytical tools in researching.

New drugs and treatment improved the survival rates of various cancers, resulting in the soaring costs of innovative technique and service needs to the increasing number of cancer survivors.24, 25 EE was served to find cost-effective care program or screening project for survivors. For example, Gordon found a telephone-delivered multiple health behavior change intervention that costs less but can improve physical activity, diet, and weight management.26 Groton selected colonos-copy bowel preparation protocols for colorectal cancer patients based on effectiveness, tolerability, and cost.27

The topic of this group is to investigate the economic value and clinical outcome by expanding nurse’s function. Two terms “Nurse Clinicians” and “Nurse Practitioners” can be seen in this group, they are considered advanced practice nurse, who has acquired the expert knowledge base, complex decision-making skills, and clinical competencies for expanded practice.28 They expanded their function in an alternative role for physician and complementary role for registered nurse.29 Therefore, EE was produced to test whether they really could help to relieve workforce shortage, reduce cost, and improve care quality. At the same time, systematic review revealed that studies about the cost-effectiveness of advanced nurse are of poor methodological quality, indicating that higher quality studies are required.30 From the terms “Patient Care Team” and “Case Management,” we can see a new nursing model is developing. “Primary Health Care,” “Home Care Services,” and “Community Health Nursing” showed us that nursing workplace is not restricted in hospital and their role is extended to community and home. These new care models need economic analysis to evaluate their effectiveness, so they become a study topic in EE.