{'fraction_non_alphanumeric': 0.029544429409111412, 'fraction_numerical': 0.014095624718087505, 'mean_word_length': 4.885202388852024, 'pattern_counts': {'":': 0, '<': 1, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Experimental study with nursing staff related to the knowledge about pressure ulcers 1

ABSTRACT Objective: to compare the scores of knowledge in teams participating or not participating in educational interventions about pressure ulcers. Method: a quantitative study with experimental design. Data were collected through a validated questionnaire. The study included 71 individuals, including nurses and nursing technicians from three intensive care units, divided into intervention group and control group. Data analysis considered the scores of the groups in the moment before and after intervention. To check the average rate of correct answers, we calculated the mean and standard deviation. We carried out the Mann-Whitney test for analysis of two independent samples, and the Wilcoxon test for related samples. Results: The mean percentage of correct answers, at the baseline was 74.1% (SD = 26.4) in the intervention group and 76.0% (SD = 22.9) in the control group and post time -intervention, was 87.8% (SD = 18.8) in the group receiving educational intervention, considering that in the control group it was 79.1% (SD = 22.2). The group that participated in educational interventions did not reach the proper average of 90% correct answers for the test. Conclusion: educational interventions on staging, evaluation and prevention of pressure ulcers contributed significantly to the increase of correct responses score in the knowledge test of the intervention group and improved their knowledge on the subject.


Introduction
In the complex environment of the Intensive Care Unit (ICU) critical health condition patients, who are comatose, sedated or unconscious are hospitalized.
Several of them are intubated and need devices to maintain stable physiological functions. These patients can be bedridden for long periods and, therefore, are more vulnerable to adverse events related to health care, such as pressure ulcer (PU) (1)(2) .
The PUs have a negative impact on the quality of life of patients, hindering functional recovery, often causing pain and suffering, leading to the development of serious infections associated with prolonged hospitalization, sepsis and mortality (3)(4)(5)(6) . Moreover, the PUs expand the workload of healthcare staff and contribute to expensive costs for health services (7) . Because of this problem, the health insurance of the Center for Medicare and Medicaid Services (CMS) -EUA -no longer reimburses the excess cost of acquired PUs during hospitalization (8) , and this may be a tendency of health plans in Brazil.
Incidence rates and prevalence of PU in Brazilian hospitals remain high while there are timid initiatives to prevent this injury. A study conducted in a public hospital in the Federal District indicated prevalence of PU in 87.5% of patients in the trauma ICU and 50% in the general ICU, and in that same hospital, the incidence of PU was found to be 41.6% in the trauma ICU and 33.3% in the general ICU (3) . Other studies in ICU in Brazil showed the incidence of 41.0% and 25.7% respectively of PU, in São Paulo and Rio Grande do Sul (9)(10) . In the international context, the United States PU prevalence rates acquired in ICUs vary from 8.8% to 12.1% depending on the type of ICU, and are considered by the authors as high rates in the US (11) . Countries in the Asian and European continents, show incidence rates of 11.2% in Japan and 14.9% in Germany (12)(13) .
The presence of PU is a classic negative indicator of care quality (14) . European and US guidelines, such as the European Pressure Ulcer Advisory Panel (EPUAP) and the National Pressure Ulcer Advisory Panel (NPUAP), provide appropriate practical recommendations, based on scientific evidence to treat and prevent the PUs (15) .
In Brazil, there are no regulations and guidelines for the prevention of PU. However, European and US guidelines are prepared for all countries and are available for the Brazilian reality (9) .
PU is a problem of multifactorial origin and involves the whole multidisciplinary team in ICUs, especially the nursing teams, offering continuous care to patients (3) .
In this regard, a routine of learning about PU should integrate the continuing education programs (EC -Continued Education Program ) in hospitals, aiming to contribute to timely and safe care in ICUs (16) . A study in Brazil shows that measuring the level of knowledge about the PU in nursing teams helps to identify the shortcomings of such knowledge and helps to guide the strategies for dissemination and adoption of preventive measures (14) . The implementation of risk assessment protocols and PU prevention correlates with a sharp decline in the incidence of these lesions (9) .
Seeking to contribute to the advancement of knowledge in this field, this research was conducted with nursing teams of three hospital ICUs of Rio Grande do Sul, aiming to compare the scores of knowledge about PU of the team who participated in the educational intervention with the scores of the team that did not participate in the educational intervention. For the definition of the groups, three tickets with the name of ICUs were drawn and a random drawing was conducted. The first two drawn ICUs were defined as the intervention group and participated in educational interventions. The last ICU drawn was defined as the control group and did not participate in educational interventions. As inclusion criteria, all the subjects who agreed to participate and signed the Informed Consent Form (ICF) were considered. As exclusion criteria, employees who were on vacation in the initial questionnaire application stage were considered.

Method
Questionnaires of subjects who expressed a knowledge score equal to or greater than 90% in the first evaluation test were not considered for the study. For the final data of the intervention group, subjects who had frequency lower than 75% in educational interventions were excluded too, but these situations did not occur.
To obtain the data, we used an instrument composed of items related to socio-demographic data and a knowledge test on PU. For this, we used The chi-square test was used to assess relationships between socio-demographic variables and knowledge as well as to verify the association of correct scores at both times. For the verification of possible differences in the scores of correct answers between the groups, we applied the Mann-Whitney test and, between the two period, pre and post, the Wilcoxon test. In all statistical tests, the significance level was α <0.05.

Results
Of the total of 74 people that participated in the  Table 1. the Pieper test, validated and adapted in a previous study in Brazil (17) . The test is validated for use with nursing professionals in the ICU. This test is based on  The intervention group and the control group showed similar socio-demographic characteristics. In Table 2   average results (14,19) .   (21) . These results highlight the importance of the continued education activities on PU with nursing professionals (9,14,(16)(17) . Therefore, it is suggested to conduct further research concerning the subject, with experimental design and control group, measuring medium and long-term knowledge of the teams, as well as seeking to understand personal and institutional factors that can be obstacles for the prevention of PU.
As a practical application of this study, it is possible to mention the positive effects of educational interventions identified by the incidence data collected in the ICU of the intervention group. Four months before the educational intervention, the incidence was 17.2% of PU and after four months of educational intervention, it was found incidence of 14.2%. Similar results were validated in a recent survey conducted in Brazil, in which the authors observed decreased incidence of PU in ICU after the implementation of a risk assessment protocol and prevention of PU (9) .
There is no consensus among authors about the ideal time interval for educational interventions.
Researchers (22) , warn about the importance of the continued education and the implementation of PU prevention programs in interdisciplinary team work 24 hours a day. The authors advise to pay constant attention to the process and conclude that the incidence of PU increases again when PU prevention programs are ignored.
The implication for the practice of intervention in this study is related to overload in the ICU environment, contributing to long periods when the researcher was waiting for the staff to perform the educational intervention. In the current study, researchers suggest that there should be less workload so that professionals can participate in educational interventions, thus contributing to the improvement of the continued education process within the ICU (23) .
A positive aspect in this study to be revealed is the