Essentials of Nursing Care in Randomized Controlled Trials of Nurse-Led Interventions in Somatic Care : A Systematic Review

Background: Nursing practice has to contribute to evidence pointing out why there is a need for more nurse-designed randomized control trials (RCTs) focusing on evidence-based practice (EBP). How far this EBP has progressed in different health aspects is usually established by systematic reviews of RCTs. Nurse-led RCTs exist but no study has addressed the essentials of nursing care. Aim: The aim was therefore to determine the essentials of nurses’ interventions by means of nurse-led RCTs in somatic care focusing on the stated context, goals, content, strategies as well as the nurse’s role related to effectiveness. Methods: A systematic review was realized according to Cochrane review assumptions to identify, appraise and synthesize all empirical evidence meeting pre-specified eligibility criteria. The PRISMA statement guided the data extraction process (n = 55) from PubMed and CINAHL. Results: Of the RCTs in somatic care, 71% showed a positive effectiveness of nurse-led interventions, of which the nurse had a significant role with regard to being the main responsible in 67% of the studies. Also, 47% of the RCTs presented a theoretical standpoint related to the nurse-led interventions and most prominent were international evidence-based guidelines. Goals were found to have either a patient-centered or a professional-centered ambition. Strategies were based on patient-directed initiatives, nurse-patient-directed initiatives or nurse-directed initiatives, while contents were built upon either a patient-nurse interaction or a nursing management plan. Conclusions: This review underlines the necessity of a holistic view of a person, as nurse-led RCTs comprising a patient-centered ambition, patient-directed initiative and patient-nurse interaction plan showed beneficial nursing care effectiveness, particularly if Corresponding author.


Introduction
Nursing practice has during the years often been based on experience, tradition and intuition rather than on scientific validation [1]. However, today's healthcare organizations as well as policy-making bodies are emphasizing the importance of evidence-based practice (EBP) [2]. Such EBP has become essential to answering a clinical question, by both awareness of the resources available to nurses and their skills in using them [3]. Still an obvious gap exists between the everyday clinical nursing practice and available empirical evidence about nursing care interventions [4]. Randomized controlled trials (RCTs) are recommended to document the effects of care and treatment [5] [6], and in nursing research to evaluate the effectiveness of nursing care interventions [7]. To ascertain the validity and reliability of RCTs, there should be a careful control regarding possible problems, i.e. dropouts, random assignment, identifying and maintaining an adequate control condition, non-adherence to protocols and assessment of clinically meaningful change [8].
Several nursing studies exist aiming to spread knowledge of how to implement EBP, starting with a description of how to search for evidence through the PICOT (Population, Intervention, Comparator, Outcome, Timeframe) format [9], and to form a critical appraisal of the studies available [10]. What seems to be lacking in several RCTs of nursing care interventions is a careful specification how the nursing care has been performed [11]. Few Cochrane reviews exist concerning nurse-led RCTs which also is evident in the somatic care. In a Cochrane review of nursing care interventions such as patient education to improve the ability of self-management, the interventions were often not clearly specified resulting in a conclusion that the evidence did not show effectiveness for the nursing care [12]. In one review concerning RCTs of nursing care interventions for secondary prevention in patients with coronary artery disease, more than half of the trials (57%) showed positive effectiveness in at least one outcome. However, there were no consistent relationships observed between intervention characteristics and the effectiveness of interventions [13]. This lack of knowledge needs to be developed by establishing not only whether something works, but also why, for whom and in what circumstances [14]. These three aspects could be enlightened by specifying the essentials of nursing care interventions in terms of context, goal, strategy and content in general as well as the significance of the registered nurse's (RN's) role in designing nurse-led RCTs (initiating, organizing, implementing, documenting) in particular. Accordingly, nursing practice has to contribute to evidence and there is an obvious need for more nurse-designed RCTs with focus on EBP [1]. How far this EBP has progressed with reference to the level of evidence in different health aspects is usually established by systematic reviews of RCTs [10]. Results from nurse-led RCTs exist but no study has so far addressed the essentials of nursing care [15]. Consequently, the aim of this systematic review was to determine the essentials of nurses' interventions by means of nurse-led RCTs in somatic care focusing on the stated context, goals, strategies, content as well as the nurse's role related to effectiveness.

Eligibility Criteria
In accordance with our aim we included nurse-led RCTs that evaluated the effectiveness of nursing care interventions in the context of somatic care; defining nurse as a RN. To narrow our target area, studies in the field of women's (gynecology/obstetrics), children's (pediatrics) and mental (psychiatric) health were excluded. Participants of interest were patients; hence studies of e.g. relatives were excluded. Outcome measures of interest were patient-reported outcome measurements (PROM) thus excluding studies focusing on e.g. cost analyses and healthcare personnel.

Literature Search
A review team of 13 nursing researchers, experienced in somatic care performed a literature search in the databases PubMed and CINAHL, with the limits to publication the last five years 2006 to 2010, the English language as the most established international and scientific language, Randomized Control Trials and age group "Adult: 19+ years". In the identification we used both controlled vocabulary (e.g. Medical Subject Headings [MeSH]) and free-text words. The MeSH-terms were "Nurse Clinicians" OR "Nurse Practitioners" and the free-text words were nurse specialist, nurse practitioner, nurse-led and nurse-managed. The literature search also excluded, with the Boolean operator NOT, the following free text words from the search: gynecology, pediatrics, pregnancy and psychiatric.In all; 244 references were found in PubMed and CINAHL and after extracting references already retrieved in PubMed, 207 were left for screening.

Study Selection and Data Abstraction
All retrieved titles and abstracts were screened to determine eligibility. Studies were excluded, if non-RCTs, only study protocols or only pilot studies. After getting full text copies publications were excluded, if non-nurseled, team-led, non-somatic care, non-patient-directed, or non-PROM (Figure 1).

Quality Assessment
The review team under the direction of first, second and last reviewers abstracted information about and reviewed the publications according to The Swedish Council on Health Technology Assessment's well-established audit template [16]. The following keywords in the audit template were considered: study population, selection criteria, sample size, power calculation, randomization strategy, comparability between groups, blinding, compliance/adherence, primary outcomes, description of intervention and control care and treatment, drop-outs, primary/secondary outcome measures, efficacy/effectiveness, side effects, results, precision, bonds and disqualification. Accordingly, the publications were graded for methodological quality from low through medium to high, the latter indicating a stronger likelihood of the RCT design to generate unbiased results.

Data Analysis
A study protocol inspired by the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement [17] was used to guide the review team through the data extraction process. The systematic review was then realized according to Cochrane review assumptions [18]; i.e. a transparent and replicable procedure attempting to identify, appraise and synthesize all empirical evidence meeting pre-specified eligibility criteria to answer a given research question. We extracted the following data: context of care, goal, strategy and content, as well as the RN's role based on at least two of four criteria (initiating, organizing, implementing, documenting). The effectiveness was based on the primary outcome stated in the studies. All reviewers scrutinized the extracted data independently followed by review team discussions concerning data quality until consensus was reached.

Demographical and Contextual Data
As shown in Table 1, over 85% (n = 47) of the 55 nurse-led RCTs in somatic care had their origin in Europe (n = 34) and North America (n = 13); more specific eight European countries were represented, whereas the Netherlands (n = 13) and UK (n = 12) had prominent positions. In all, four continents were represented; besides Europe and North America, also Asia (n = 6) and Oceania (n = 2). Eight care contexts in somatic care were identified among the 55 RCTs whereas cardiac care (n = 18) and primary care (n = 10) were the two most prominent ones ( Table 1).

Goals, Strategies and Content
Forty-seven percent (n = 26) of the RCTs in somatic care presented a theoretical standpoint related to the nurseled intervention ( Table 2) and most prominent were international evidence-based guidelines (n = 9). As displayed in Table 3, goals were abstracted into two main categories; a patient-centered ambition and a professional-centered ambition, both comprising almost equal number of categories, i.e. goals. The most prominent goal with the patient-centered ambition was quality of life (n = 11) while prevention was the most common goal as to the professional-centered ambition (n = 15). Strategies were abstracted into three main categories; patient-directed initiatives, nurse-patient-directed initiatives and nurse-directed initiatives ( Table 3). Nurse-patient-directed and nurse-directed initiatives comprehended nearly three times more categories, i.e. strategies than patient-directed initiatives. The most prominent strategy for patient-directed initiatives was video/telemonitoring (n = 4) while the corresponding figures for nurse-patient-directed and nurse-directed initiatives were dialogue (n = 14) and assessment (n = 17), respectively. Contents were abstracted into two main categories ( Table 3); a patient-nurse interaction and a nursing management plan, both comprising close equal numbers of categories, i.e. contents. The most prominent content for patient-nurse interaction plan was support and counselling (both, n = 7) while follow-up/feedback (n = 10) was the corresponding content for nursing management plan.

The Nurse's Role and Its Effectiveness
In all, 71% of the RCTs in somatic care (n = 39) showed positive effectiveness of a nurse-led intervention, of which the nurse had had a significant role with regard to being the main responsible in 67% (n = 26) of the studies. Furthermore the theory-based RCTs presented a higher figure (20 of 39; 51%) with regard to positive ef-  fectiveness compared to the non-theory-based RCTs (6 of 16; 38%). The RCTs with positive effectiveness showed prominent figures as to patient-centered ambition with regard to goal, nurse-directed and nurse-patientdirected initiatives with regard to strategy, and patient-nurse interaction with regard to content ( Table 4). These figures should be compared to RCTs without effectiveness showing more prominent figures at professionalcentered ambition (goal), at nurse-directed initiatives (strategy) and both at patient-nurse interaction and nursing management plans (content).  Quality of life (11) Self-management (9) Self-care behaviour (5) Patient satisfaction (3) Patient-centered ambition (28) Video/telemonitoring (4) Self-monitoring (3) Practical training (1) Patient-directed initiatives (8) Counselling (7) Support (7) Empowerment (6) Advice (6) Education (2) Motivation (1)

Methodological Issues
It is interesting and remarkable that less than one-third of the RCTs identified reached the final review process indicating the importance of setting up inclusion and exclusion criteria as well as quality assessment, even in "the RCT world". At the same time it is of importance to remember that also qualitative designs are essential in nursing to identify patients' needs and desiderata in order to develop the most appropriate and effective PROM interventions [74]. A possible limitation was that only two data bases were screened with regard to nurse-led RCTs; but it is important to stress that these data bases were the most relevant ones-CINAHL and PubMed for the purpose of nurse-led interventions in somatic care. Another possible limitation was to study the phenomenon in just one context; the somatic one. From a methodological standpoint it is essential to handle data in a proper way with a sufficient review competence; in this case it was likely so, as all reviewers were researchers familiar within the somatic care context. Of course it would be of value to compare if, and in what way nurse-led RCTs in somatic care differ from the context of women's, children's and mental health. Another limitation is the extensive review team with a risk of bias in the extraction and interpretation processes; but at the same time the review process was guided by an established study protocol [16] as well as the Cochrane review assumptions [18] implying that every single review was scrutinized by the review team until negotiating consensus was reached. It is also a risk to make a fair and proper decision concerning effectiveness or not, due to the studies' choice of primary outcome and the magnitude of clinical relevance and utility from a nursing perspective. Also to determine the nurse's role was sometimes limited due to scanty descriptions of the nurse-led interventions especially with regard to nurses' functions both in a partial and a holistic perspective.

Nursing Care Intervention Issues
Considering the fact that most of the nurse-led intervention studies have been carried out in Europe and North America, it is questionable how well the results are generalizable outside these areas. On the other hand the need for more nurse-led interventions has been emphasized [7], and this seems particularly true for all countries. It is also striking that two care contexts in somatic care stand out; cardiac care and primary care. Both are typical fields engaging both clinical and academic nurses, and the range of lethal diseases like coronary artery disease is extensively engaging both professional interests and socioeconomic resources [13] while the primary care has an increased responsibility for the public health including the whole flora of symptoms, conditions and diagnoses of acute as well as chronic characters [6]. It is satisfactory that as much as 71% of the nurse-led RCTs ended up with a beneficial nursing care [13], indicating what already has been pointed out [75]. A good reason why nurse-led interventions are successful is obviously the holistic view of the person, e.g. a person-centered care covering all aspects of the person [76] [77]. RCTs with a person-centered care are showing promising figures [5] [78]. Our review underlines this holistic view of a person as RCTs comprising a patient-centered ambition, patient-directed initiative and patient-nurse interaction plan were more prevalent in the nurse-led RCTs with beneficial nursing care effectiveness compared to those without effectiveness. Also that the nurse's role was of significance in two-thirds of these nurse-led RCTs substantiating that the holistic view, i.e. a person-centered care is of importance and a necessity in order to counsel, support, and follow-up the patient in maintaining health or preventing or recovering from disease [79] [80]. Besides the holistic perspective involving a participating patient in his/her total care situation, the person-centered care also advocates the need for and use of EBP [77]. Accordingly, such reasoning highlights the necessity of using theoretical standpoints when operationalizing the study design by using appropriate measurements in order to establish both relevant and effective outcomes. As our study indicates, the theory-based studies (51%) brought more effectiveness than the non-theory-based ones (38%), but the use of theory-based strategies is still premature [77]. A theory-based nurse-led RCT intervention points out the grounds in planning and developing the context, goals, strategies, content as well as the nurse's role related to estimated effectiveness.

Conclusions and Implications
Nurse-led RCTs with a distinct and clear patient-centered ambition, patient-directed initiative and patient-nurse interaction plan seem to promote beneficial nursing care effectiveness. Also a sound theoretical frame was seen to be of importance when designing a nurse-led RCT. Accordingly, more nursing care interventions in nurse-led RCTs are needed and can advantageously and theoretically be based on for example a person-centered care. Basic theoretical perspectives are essential when planning and developing evidence-based practice as well as elucidating the role of the nurse in relation to the estimated effects. Concerning effectiveness of nursing care interventions, more reviews are needed in order to compare nurse-led RCTs in somatic care with mental health as well as women's and children's health.