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A Quasi-experimental Study to Assess an Interactive Educational Intervention on Nurses’ Knowledge of Pressure Ulcer Prevention in Nigeria

Empirical Studies

A Quasi-experimental Study to Assess an Interactive Educational Intervention on Nurses’ Knowledge of Pressure Ulcer Prevention in Nigeria

Index: Ostomy Wound Manage. 2016;62(4):30-40.


Educational intervention programs are an important element to improve nurses’ knowledge of pressure ulcer (PU) prevention. Various teaching methods have been used with diverse results but none have been analyzed in Nigeria. A quasi-experimental study using a pretest/post test design was conducted among 193 registered nurses with >6 months experience who worked in purposefully selected wards (neuroscience, orthopedics, renal, and cardiac) in 3 teaching hospitals to examine the level of knowledge retention after interactive instruction.Participants were randomized to intervention (IG, n = 127 from 2 hospitals) and control (CG, n = 66 from 1 hospital) groups; the IG was provided a 5-day, face-to-face interactive lecture, and the CG engaged in a 1-day, 4-hour discussion of PU prevention practices. The Pressure Ulcer Knowledge Tool, a 47-item questionnaire in which a correct answer = 1 point and an incorrect/“I don’t know” answer = 0 (maximum score 47), was used to assess and compare knowledge retention at 3 time points: baseline (T1), immediately after instruction (T2), and after 3 months (T3). Three trained research assistants assisted with registration of participants and distribution and collection of the questionnaires. All questionnaires were retrieved at T1 before the intervention began. Respondents were encouraged to respond to all questions. Data were analyzed using t-test and ANOVA (P = 0.05). At T1, knowledge scores were comparable between the IG and CG (32.5 ± 4.2 and 30.8  ± 5.0 for IG and CG, respectively). At T2, knowledge scores increased significantly only in the IG to 40.7 ± 3.4 (d = 1.94, P <0.05). The mean difference between T1 and T2 was  -8.2 ± 5.4, t = -17.0, P = 0.000. Similarly, mean scores increased significantly from T2 to T3 in the IG (mean= -2.0 ± 5.5, t = -4.1, P = 0.000); scores in the CG were -6.2 ± 7.2, t = -6.3 (P = 0.000). A face-to-face interactive lecture was shown to be an effective method of program delivery for nurses; other educational methods should be assessed and their effects on PU prevention practices and outcomes evaluated.  


Pressure ulcers (PUs) are a significant threat to the safety of patients and have a major negative impact on patients, their families, and the health care system.1,2 Findings from a cross-sectional observational study1 conducted among 2,000 patients in a tertiary care hospital in Australia confirm PUs were responsible for prolonged hospital stay and increased economic cost. According to a systematic review and meta-synthesis,3 PUs have a substantial impact on health-related quality of life among older patients. A prevalence study by Mclnerney4 showed the risk of mortality is 2 to 6 times greater in patients with PUs as opposed to persons without PUs.3,4 The negative effects may be even greater in the poorer nations of the world, particularly among patients with spinal cord injury. According to Zakrasek et al’s review of the literature5 on risk factors and cost of PU in low- and middle-income countries, the prevalence of PUs is high and comes with increasing complications.  

Various strategies regarding education and training for nurses have been shown to be factors in PU prevention.6-8 For example, Tweed and Tweed6 conducted an educational intervention study among critical care nurses (N = 62) and reported an increase in knowledge for PU prevention post intervention. Using a pretest/post test design, Cox et al7 compared the effectiveness of 2 methods of instruction on PU prevention among critical care and medical surgical nurses and found knowledge retention can be maintained by a quarterly educational program. These educational programs have produced good outcomes, such as reduced PU incidence,6,9 effective risk assessment, successful  planning, and implementation of interventions.10-12 

Despite these findings, evidence from the literature suggests nurses’ level of PU knowledge is not yet optimal.13,14 For example, although a systematic review13 of the effectiveness of educational programs in promoting knowledge among nurses for PU prevention showed educational programs have positive effects on nurses’ knowledge of PU prevention, similar reports of descriptive studies15,16 in Nigeria suggested inadequate knowledge of PU prevention among nurses in Nigeria. Such reports point to a need for repeated education and training as new information on PUs emerges for Nigerian nurses. 

Literature Review

The joint international organization for PUs17 asserts a number of contributing or confounding factors, yet to be fully elucidated, are associated with PU development, underscoring a need for consistent attention to issues regarding PUs. Patient quality care and safety organizations have focused on PU prevention issues. For example, the American Nurses Association Quality Forum18 recognized PUs as largely preventable, nursing-sensitive adverse events. The Joint Commission on Accreditation of Healthcare Organization19 included PU prevention as one of the National Patient Safety Goals. The strong position on PU prevention taken by these organizations commends programs that provide PU updates for nurses because nurses play significant roles in PU prevention. Quasi-experimental, pretest/post test and descriptive studies20,21 confirm that inadequate knowledge and skills for PU prevention among nurses working in acute care facilities can significantly influence PU rates13 and patients’ clinical outcomes. This is evident in Nigeria, where hospital-based surveys22-25 reported increased PU incidence rates are attributed partly to inadequate knowledge of evidence-based preventive interventions among care providers, particularly nurses. This conclusion was corroborated by other authors,15,16 who reported knowledge about PU prevention among nurses was less than optimal. 

Continuing education is vital to consistent, safe, and effective care delivery and also a prerequisite for reconfirmation of practice licenses in most countries.26,27 Specifically, continuing education comprises activities that increase the knowledge of workers toward improved performance.28 Different strategies including face-to-face lectures are employed in continuing education programs. Traditional lectures are typically teacher-focused, one-way communication, which leaves the learners inactive and passive.29,30 According to quasi-experimental studies involving nurses,28,31,32 the duration of knowledge retention by learners participating in the lecture method is short, usually no longer than 8 weeks, even with the use of PowerPoint® delivery. Based on this limitation, educational experts33 suggest integrating diverse or blended methods in any one teaching session for better outcomes.

Teaching theories. Adult, professional learners such as nurses would benefit from blended strategies, because these learners are self-directed and need to have control over their learning needs.34 Nursing professionals need to incorporate learning into their busy schedules to effectively  understand and be current with increasing research evidence in health care, which also drives health care improvements. Some descriptive studies35,36 involving medical students suggest when professionals are engaged in learning, they reflect on previous experiences to bring meaning to the new knowledge, enhancing the learning experience. To facilitate reflection and better understanding of new knowledge, particular delivery strategies should be incorporated into a professional continuing education program. According to Sandars’37 review on the concept of reflection,37 reflection is a metacognitive process that creates better understanding of both the self and the situation to inform future actions. As such, reflection is a major component of life-long learning and believed to improve professional competence. Experience is significant in professional learning, but it is not a stand-alone phenomenon. Drawing from Kolb’s38 theory of experiential learning, experience must be integrated into an existing knowledge structure to become new and expanded knowledge. This process requires the skill of reflection for a higher level of personal learning, such as when an individual learns about the side effects of a drug by observing reactions (experience) from a patient on the drug or when the clinician becomes more adept at a clinical skill after an experience demonstrating ineffective application of the skill. 

Interactive lecture is a form of inquiry learning that allows active learner participation and reduces the monotony of passive learning that occurs with the traditional lecture.39 Interactive lecture is implemented using methods such as brainstorming, small group discussion, role play, and simulations,40 enhancing student engagement with their course materials. Interactive lectures also may take the form of questioning the audience or using engagement triggers to stimulate interest and arouse the learner’s attention and serve as ice breakers.41 In his review of the literature describing the indicators of interactive learning, Steinert and Snell41 noted active participation of learners is a prerequisite for learning beyond the recall of facts. On a broader perspective, Lee42 acknowledged interactive learning  encompasses every method except traditional lecture. The effectiveness of the interactive mode of learning has been well documented as a preferred method to the traditional lecture. However, to the best of the authors’ knowledge, its effectiveness in delivering PU prevention education in Nigeria has not been documented. 

The aim of this study was to examine the effectiveness of a face-to-face, interactive lecture approach to education on knowledge retention among nurses in selected teaching hospitals in southwest Nigeria.

Four (4) research questions were raised: 

1. What is the knowledge of PU prevention strategies of the intervention and control groups at baseline?

2. What is the effect of interactive lecture on post test knowledge score in intervention and control groups?

3. What is the difference in post test scores immediately (T2) and 3 months (T3) post intervention in the intervention group?

4. What is the effect of selected demographic characteristics (years of experience, professional cadre based on profession, previous exposure to PU lecture) on knowledge score in the 2 groups before and after educational intervention?

Methods and Procedures 

The study adopted a nonequivalent control group, pretest/post test design and was conducted in 3 selected teaching hospitals in 3 (Oyo, Osun, and Lagos) of the 6 states in the southwest geopolitical zone in Nigeria. The hospitals included the University College Hospital (UCH) and Lagos State University Teaching Hospital (LASUTH), Ibadan; and Obafemi Awolowo University Teaching Hospital Complex (OAUTHC), Ile Ife. The hospitals were under 2 main clusters based on proprietorship: state government-owned and federal government-owned, publicly funded institutions. All of  the hospitals are large tertiary institutions, with a minimum of 300 beds each. Ethical approval was sought and obtained from the Health Research and Ethics Boards of each institution. 

A purposive sampling of the hospital was conducted based on inclusion criterion of providing care for patients with complex health problems. Balloting was done to determine which hospitals served as intervention and control groups. The intervention group (IG) included nurses from LASUTH and UCH, and the control group (CG) included nurses from OAUTHC. To limit inadvertent influence of treatment condition on the CG, the IG was completely separate from the CG. 

Participating wards also were selected purposively to reflect patients with health problems that would likely place them at risk for PUs; as such, all nurses from the surgical (orthopedics), medical, and neurological wards (except nurses on vacation) were invited to participate. 

Testing instrument. The Pressure Ulcer Knowledge Test (PUKT)43 was used to assess knowledge and information acquisition at the 3 testing time points. The tool is composed of 47 items that measure respondents’ knowledge of risk factors, preventive strategies, and PU staging. Correct Yes/No responses are scored 1 and incorrect responses of Yes, No, or I don’t know are scored 0. The maximum score is 47 (100%).  

The PUKT has been used in other countries9,44 with reported good reliability levels. A pilot survey was conducted in a different state teaching hospital (Ogun state) among 111 nurses 6 months before the main study to examine the feasibility of the study and to test the reliability of the testing tool.16 Findings from the pilot study led to the revision and rewording of some items in the instrument for clarity and in relation to the care environment. For example, in the local hospital, nurses use water-filled gloves to elevate the heels. Therefore, the item in  the original document that reads Heel protectors relieve pressure on the heels  was reworded to read A heel protector such as water-filled glove effectively relieves pressure on the heels. In addition, the item that relates to the appointment of a governmental panel to study PU risk, prevention, and treatment were removed because it was not applicable to Nigeria. This was the first time the PUKT was validated in Nigeria. The reliability coefficient was found to be 0.82. 

General procedure. In each setting, with the support of the Director of Nursing services, the pretest (paper-and-pencil PUKT) was administered to all participants at the same time. This was to ensure the uniformity of nurses’ entry behavior and to establish their level of PU knowledge at baseline (T1) to accurately examine the effect of the program. Each participant signed a register to document attendance. The researcher recruited and trained 3 research assistants (RAs) to assist with participant registration and to monitor and retrieve completed questionnaires. 

Study group procedure. The nature, purpose, and procedure of the study were explained to nurses who provided written consent for participation. The IG participants  (UCH and LASUTH) were invited to attend the educational workshop organized in the respective hospitals. 

The program was structured to accommodate various nursing schedules because it was not possible to take all nurses off the wards at the same time to attend the 4-hour workshop. In UCH, the nurses were divided into 2 groups. Each group attended the workshop for 5 consecutive days. In LASUTH, all participants attended the same 5-day workshop facilitated by a labor conflict that decreased patient load.

Intervention fidelity was maintained because the module curriculum was followed strictly by the principal investigator, who also delivered all the sessions. 

The interactive educational program. Participants were provided the program of events for each day. They were encouraged to choose an identification number to facilitate analysis in matching each participant’s pretest with post test scores, to assess full participation, and to easily identify missing questionnaires. The intervention was an interactive lecture that involved small group discussions and brainstorming. Participants were grouped based on the wards where they work to facilitate continual cooperative work on the wards. During the first 15 minutes of each module, participants brainstormed on specific questions and answers and shared experiences and practical ideas on PU prevention. The remaining period was used for lectures and discussion on current trends regarding PU prevention and related clinical correlations. For example, the researcher projected pictures of different stages of PUs and participants were asked to determine the stages. This helped actively involve participants in the sessions. Lectures were projected using PowerPoint® slides. The principles of adult learning34 guided the interaction with the participants (ie, learners connect learning with past experience). To facilitate this connection, the researcher also displayed different skin care products (eg, dimethicone-based barrier creams and sprays, dressings, foams, and corn starch) to stimulate discussions on nurses’ practices. At the end of the sessions, paper versions of the PowerPoint® slides were provided to participants. The level of each respondent’s participation was not documented or measured.

All modules were presented by the principal investigator in the 2 hospitals. Each session lasted for 4 hours per day. The curriculum consisted of 5 modules as shown in Table 1

Assessment. A pencil-and-paper PUKT was readministered on day 5 as an immediate post test (T2). The test was completed under supervision, and participants did not refer to the paper versions of the slides. Completed tests were retrieved on the spot. Participants were informed they would be invited to a third round of testing after 12 weeks (T3).  

Participants returned to their respective wards but maintained the groupings to facilitate cooperative problem-solving while providing care. Over the 12-week between-test period, the researcher reinforced what was covered in the module with hands-on demonstrations. At the end of 12 weeks, participants were contacted by telephone, Short Message Services, and email for the second post test. The same test (PUKT) was administered at all 3 time points. 

Control group procedure. The CG also was provided study details. The PUKT questionnaire was distributed to the participants to examine their baseline knowledge. The participants engaged in a general 1-day, 4-hour discussion on their usual practices for PU prevention. The session was facilitated by the RAs under the supervision of the principal investigator. This was followed by a second test (T2). Participants were contacted for the second post test at 3 months (T3). 

At the end of the third data collection (which marked the end of the study), the CG was provided the same package of educational materials as the IG on PU prevention for ethical reasons. 

Data analysis. Data from the PUKT instrument were collected and entered into a database, the Statistical Package for Social Sciences (SPSS) (Version 17.0, Chicago, IL), for analysis. Data were checked to ensure consistency and to determine where information was missing. A complete case-wise analysis was performed for missing data because the proportion of missing data categorized as Missing Completely at Random (MCAR) was <10% and  was observed only at the 3-month post test (T3). Descriptive statistics using absolute number and relative frequencies (percentages) to describe the sample characteristics were used. Means and standard deviations were computed to ascertain nurses’ PU knowledge scores. A paired sample t-test was used to compare the differences in knowledge between IG and CG pre- and post intervention. Cohen’s d was calculated to determine the strength of the intervention effect. The effect of selected demographic variables on participants’ knowledge scores was examined using ANOVA, and the effect size (eta squared) also was computed. The level of significance was set at α = 0.05% 


Demographic characteristics. The sample consisted of 193 registered nurses, 127 in the IG and 66 in the CG. The level of education and areas of practice are described in Table 2. The majority of the respondents were basic diploma-certified registered nurses (RN) (133, 68%) and degreed nurses (BNSc) (26, 13.5%); a statistically significant difference was noted in both the IG (36.8 ± 10.3, P = 0.03) and CG (35.2 ± 11.9, P = 0.04). A similar trend was found with years of experience between IG and CG (14.5 ± 13.7, P = 0.04 and 12.6 ± 12.0, P = 0.03, respectively).

Baseline knowledge. The mean knowledge score at baseline was comparable in both IG (32.5, SD = 4.2) and CG (30.8, SD = 5.0), as shown in Table 3

Knowledge retention. The score at T2 significantly increased only in the IG from 32.5 ± 4.2 to 40.7 ± 3.4. In the CG, the T2 score did not increase significantly (31.2 ± 5.2, effect size, Cohen d = 1.94). At 3 months (T3), a further increase in knowledge score was observed in the IG from 40.7 ± 3.4 to 42.7 ± 4.0, P <0.001) and in the CG from 31.2 ± 5.2 to 37.8 ± -6.3 (P <0.001) (see Table 3).

Using a paired sample t-test to compare results between the IG and CG from T1 to T2 and T3, the increased mean difference in knowledge scores was noted to be significantly higher in the IG than in the CG (-8.2  ± 5.4, t = -17.0, P <0.001, d = 0.385) (see Table 4), suggesting the intervention accounted for 38.5% of the change in knowledge scores. 

Effect of selected demographic characteristic. The effect of selected demographic characteristics (eg, years of experience, professional cadre, and previous exposure to a PU lecture) on respondents’ scores pre- and post intervention was determined using one-way ANOVA. Findings were not significant (see Table 5). An examination45 of the combined effect (interaction) of selected respondents’ factors (eg, years of experience, previous exposure to PU lecture) on the post test scores using a one-way ANOVA showed a significant interaction effect with previous exposure to PU education (F[1,192] = 2.781, P <0.05). However, the interaction effect with both years of experience and professional cadre was not significant (P >0.05).


The aim of this study was to examine the effectiveness of a face-to-face, interactive PU lecture approach to education on knowledge retention among nurses by comparing pretest and post test knowledge scores. The major hypothesis was that nurses will be able to retain knowledge for 3 months post intervention better than nurses who were not exposed to a similar learning method. The intervention was carried out in the same manner by the researcher in all the settings using the modules designed for the program. Participants were selected from neurology, orthopedic surgery, and medical inpatients units because reports from previous studies indicated the risk of PU was higher in patients admitted to these units as a consequence of impaired physical mobility.45 Results of Niederhauser et al’s46 systematic review of literature underscored the importance of PU educational programs in successful implementation of preventive protocols.  

The current study showed nurses had some basic knowledge about PU prevention because they were experienced practitioners. However, after the interactive lecture, the knowledge level increased significantly in the IG as compared to what was observed in the CG.   In addition, participants were able to retain the knowledge acquired as indicated by the mean scores at the 3-month follow-up. This suggests the intervention was effective. In contrast to these findings, reports from previous quasi-experimental studies30,31 involving nursing and medical science students showed students tend to forget ~80% of presented education within 8 weeks of a lecture. The current findings showed knowledge of PU prevention was sustained for 12 weeks (3 months) post intervention among the study cohort, as well as in the CG. This sustained knowledge retention may be linked to the fact respondents in both groups were adult learners, with varied previous experiences and learning they brought to the fore. In addition, hands-on experience and reinforcement of what was learned during the follow-up period in the IG could have contributed to the sustained knowledge 

Khatoni et al’s47 pretest/post test study among nurses (N = 140) suggested both lecture and elearning methods are effective in increasing students’ knowledge. Although opinions tend to differ regarding the most effective method of teaching, evidence supports the effectiveness of interactive lectures, which enhance active student engagement and participation and demonstrate more positive learning gains than traditional lecture methods. For example, from results of their study, Prince and Felder39 proposed inductive learning methods, including cooperative or team learning, active learning, case studies, projects, or presentations, are more effective than the traditional lecture. 

In this study, sustained knowledge retention may be explained using the principles of cooperative learning as proposed by Johnson et al.48 Accordingly, the authors described cooperative learning as the instructional use of small groups to facilitate students’ working together to maximize their learning through mutual dependence rather than competition. It is proposed such learning strategy promotes deep understanding of the subject matter and enhances knowledge retention. It follows that within the small groups, participants can easily exchange views and develop self-confidence. Johnson and Johnson49 also believed working/learning in small groups works among health care professionals to help develop communication skills essential for building stronger communication with patients.  

In the current study, participants worked in small groups based on their respective wards. During the 3-month follow-up period, the researcher visited the nurse participants on the wards weekly, and teaching was reinforced at the bedside to promote evidence-based practice. The practice component is not part of this current report. The authors strongly believe the small group discussions and the supplemental printed materials (ie, PowerPoint® slides) sustained the interactive learning and also enhanced self-instruction and knowledge retention. Additionally, participants were experienced practitioners. Goldberg et al’s50 pretest/post test study (N = 130) noted interactive lecture increased students’ self-efficacy, which is  associated with academic achievement. Similarly, Knight and Wood’s51 pretest post test study (N = 700) to compare the learning gains between traditionally taught lecture and interactive classroom format concluded collaborative work in student groupings and discussions significantly increased learning gains and conceptual understanding. Furthermore, Prince and Felder39 noted a strong motivation to learn when learners clearly perceive a need to know. It follows that learners’ perception of their specific learning needs influences the motivation to learn. The findings in the current study also can be explained by Kolb’s38 model of experiential learning, which hypothesized that concrete experience allows for reflection (ie, incorporation of experience with teaching). The current study authors assert such reflection was demonstrated by study participants, which possibly also strengthened their ability to recall new knowledge, as observed only in the IG. 

Adult learners have previous experiences that help illuminate a new learning situation. As such, the current study examined the interaction effect of treatment, years of experience, and exposure to previous PU lectures on post test scores in the IG and CG. The findings indicated a significant difference, suggesting the educational intervention accounted for the difference in post test scores and was not independently determined by demographic characteristics. This finding is consistent with Hulsenboom et al,52 whose cross-sectional, comparative study among nurses (N = 522) concluded demographics, including age and nurse experience, had no significant influence on knowledge of PU preventive interventions. 

Nurses play a significant role in PU prevention, requiring ongoing acquisition of knowledge. Because the interactive lecture contributed significantly to knowledge retention, a more consistent use of interactive methods of teaching, such as case presentations, brainstorming, and small group discussions, is suggested for continuing nurse education.


The present study was conducted among nurses in 3 tertiary institutions. A study with a wider scope that may include nurses in secondary care facilities is warranted. In addition, comparison of the effectiveness of lecture with other methods of program delivery also should be considered. 

Limitations also include the fact the interactive face-to-face lecture method was compared with only 1 other method of program delivery (discussion group), so the findings should be interpreted with caution. Additionally, the pretest/post test design of this study limits the degree to which the results may be attributed to the effects of the intervention (ie, the authors had no control over natural events in the comparison group hospital). Therefore the effects of history may be a threat to internal validity. In this vein, history describes events that occur concurrently with the treatment, which the researcher may not have control over, thereby influencing the results obtained. In the current study, the possibility of another educational program in the CG institution during the period of this study that could provide information on the subject matter to respondents cannot be ruled out. To the best of the authors’ knowledge, the CG participants were not exposed to another learning situation except that the intervention package was provided at the end of the study to the CG participants. Finally, knowledge retention was monitored for only 3 months post intervention.


A pretest/post test study was conducted to measure gains in knowledge retention for nurses following an interactive lecture on PU prevention. The results demonstrate an interactive lecture using small groups can effectively facilitate knowledge retention among nurses in a continuing education program. The effect of intervention was significantly higher in the IG than in the CG. Interactive engagement of nurses and inductive methods of instruction for program delivery appear to be successful approaches in continuing education programs for nurses. Future studies are needed to examine how acquired knowledge translates into effective PU prevention practices and influences clinical outcomes. 


Dr. Ilesanmi is a lecturer and a certified wound care nurse, Department of Nursing; and Prof Oluwatosin is a Professor of Plastic and Reconstructive Surgery, Department of Surgery, College of Medicine, University of Ibadan, Ibadan, Nigeria.


Please address correspondence to: Dr. Rose Ekama Ilesanmi, Department of Nursing, University of Ibadan, Ibadan, Nigeria; email: