Development of the Acute Care Nurse Practitioner Competencies Scale: An Exploratory and Confirmatory Factor Analysis.

BACKGROUND: Nurse practitioners (NPs) play a vital role in healthcare, particularly in acute care settings in Taiwan. The professional competencies of NPs are essential for providing safe and effective care to patients. To date, no measurement tool is available for assessing the clinical competencies of NPs in acute care practices. PURPOSE: The aim of this study was to develop and investigate the psychometric properties of the Acute Care Nurse Practitioner Competencies Scale (ACNPCS). METHODS: Mixed-method research was employed using samples of experienced NPs. First, we used a focus group of seven experienced NPs who worked for medical centers, community hospitals, and regional hospitals to identify clinical competencies content. Second, we implemented consensus validation using two rounds of the Delphi study and revised it to a 39-item ACNPCS. Third, we conducted content validity with nine NP experts and modified the competency content to 36 items. Finally, we conducted a national survey of 390 NPs from 125 hospitals to determine the extent to which the NP competency content relates to their clinical practice. To examine the reliability of the tool, we tested the internal consistency reliability and test-retest reliability. Exploratory factor analysis, confirmatory factor analysis, and known-group validity were used to test the construct validity of the ACNPCS. RESULTS: The Cronbach's alpha coefficient for the overall scale was .92, with subscale coefficients ranging from .71 to .89. Test-retest reliability showed the two scores of the ACNPCS on the two occasions tested to be highly correlated ( r = .85, p < .001). Exploratory factor analysis revealed that the scale had six factors: providing healthcare, evaluating care, collaboration, education, care quality/research, and leadership/professionalism. Factor loadings for each factor item ranged from .50 to .80 and explained 72.53% of the total variance in the NPs' competencies. Confirmatory factor analysis indicated that the six-factor model showed satisfactory model fit (χ 2 = 780.54, p < .01), and the fit indices met the standards for adequate fit (goodness-of-fit index = .90, comparative fit index = .98, Tucker-Lewis index = .97, root mean square error of approximation = .04, and standardized root mean residual = .04). Known-group validity revealed that the total scores for novice NPs differed significantly from those of expert NPs in terms of the competencies ( t = 3.26, p < .001). These results validated the psychometric soundness of the newly developed ACNPCS. CONCLUSIONS: The newly developed ACNPCS exhibited satisfactory reliability and validity, supporting the use of the ACNPCS as a tool to assess the clinical competencies of NPs in acute care settings.

Key determinates of job satisfaction for acute care nurse practitioners in Taiwan.

BACKGROUND: Taiwan is a super-aged society, and the shortage of hospital doctors; nurse practitioners (NPs) became vital healthcare providers to fulfill the healthcare demands of the population. The purpose of this study was to explore the key determinates of job satisfaction for NPs in acute care practices using significant practice variables, such as empowerment and burnout. METHODS: Participants of this descriptive survey study were recruited from a national sample of NPs with membership in the Taiwan Association of Nurse Practitioners. The data were collected utilizing an online questionnaire based on demographic and practice variables, the Misener Nurse Practitioner Job Satisfaction Scale (MNPJSS), the Condition for Work Effectiveness Questionnaire II (CWEQ II), and the Copenhagen Burnout Inventory (CBI). A total of 1,211 NPs completed the online survey. A multiple regression model with the stepwise selection was used to explore job satisfaction. RESULTS: The mean overall satisfaction score indicated that the level of satisfaction was between slightly dissatisfied and slightly satisfied. Regression results indicated that formal power, work-related burnout, access to information, and needed resources were critical components of job satisfaction, and accounted for 63% of the variance. Moreover, NPs who were married, had a higher annual salary, worked only during the day shift, and had lower patients-related burnout showed better job satisfaction. CONCLUSIONS: This study provides evidence for healthcare organizations to formulate policies to strengthen NP job satisfaction. Empowerment and burnout are vital factors in NPs' job satisfaction. Healthcare organizations have an obligation to implement policies to empower NPs in practice and provide interventions to mitigate burnout. Implementing these changes will improve job satisfaction and with it the quality of patient care.

Comparing Prodrugs with Acyclovir for Treating Postherpetic Neuralgia among Herpes Zoster Patients: A Systematic Review and Meta-Analysis.

Postherpetic neuralgia (PHN) is a common, painful, and long-term complication of herpes zoster (HZ). PHN increases the demand for healthcare services and, previous studies showed that patients who received antiviral agents were less likely to develop PHN. The objective of this study was to compare the efficacy of prodrugs and acyclovir in treating PHN among patients with HZ. The search included the PubMed, Medline, Embase, and Cochrane Center of Register of Controlled Trails databases through February 2022. Clinical trials and randomized controlled trials (RCTs) involving antiviral agent intervention for HZ patients diagnosed with PHN were eligible for inclusion. A meta-analysis was conducted to calculate pooled risk ratios (RRs) with 95% confidence intervals (CIs) with a fix-effect model. Five RCTs with 1147 HZ patients met our eligibility criteria. Our meta-analysis found that there was a significantly lower risk of PHN for members of the prodrugs group (famciclovir and valaciclovir) compared with those who received acyclovir (RR = 0.86, 95%, CI: 0.75 to 0.98, p = 0.03). The review of studies indicated that the efficacy of prodrugs was better than acyclovir for reliving PHN.

The impact of organisational commitment and leadership style on job satisfaction of nurse practitioners in acute care practices.

AIM: This study aimed to determine the main factors that affect nurse practitioners' (NPs) job satisfaction, especially the relationship between organisational commitment and leadership styles in acute care practices. BACKGROUND: There is little known about the influence of organisational commitment and leadership on NPs' job satisfaction within acute care hospitals. METHODS: A cross-sectional design with a national online survey enrolled 1205 NPs from the Taiwan Association of Nurse Practitioners. A multiple regression model was applied to identify potential variables that associated with job satisfaction. RESULTS: Organisational commitment (mean = 59.47), job satisfaction (mean = 173.47) and leadership style (mean ranged from 13.29 to 28) were at a moderate level. Organisational commitment, leadership style, patient load and NP advancement levels explained 63% of the variance in NPs' job satisfaction. CONCLUSIONS: Organisational commitment and leadership styles, such as idealized influence and individual consideration, are major factors that impact NPs' job satisfaction. IMPLICATIONS FOR NURSING MANAGEMENT: Health care organisations should develop policies targeting organisational commitment and managers' leadership styles to improve NPs' job satisfaction.

Effects of Professional Autonomy and Leadership Style on the Team-Based Practice of Acute Care Nurse Practitioners in Taiwan.

BACKGROUND: Little is known regarding the factors that affect the team-based practice of nurse practitioners (NPs). Examining the relationships between these factors and team-based practice may provide important insights into the strength of the NP practice. PURPOSE: This study was designed to examine the effects of practice autonomy and leadership style on the team-based practice of acute care NPs working in hospitals. METHODS: A cross-sectional, national survey design was conducted to examine the autonomy, leadership, and team-based practice of NPs. One thousand three hundred ninety-one NPs completed the questionnaire, which included demographic and practice variables, the Dempster Practice Behavior Scale, the Multifactor Leadership Questionnaire, and the NP-physician relations subscale of the Nurse Practitioner Primary Care Organizational Climate Questionnaire. The hierarchical linear model was used to differentiate between the NP-level and organization-level effects on team-based practice. Multiple regression was applied to explore the factors associated with team-based practice. RESULTS: The hierarchical linear model results identified no organization-level effect on team-based practice. Moreover, the results of the regression model found that NPs with greater autonomy in actualization, empowerment and readiness, and idealized influence leadership style enhanced the performance of the doctor of medicine-NP team-based practice. The final model explained 39% of the variance in doctor of medicine-NP team-based practice. Autonomy in actualization and empowerment were identified as the two most important predictors. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: The practice autonomy and leadership style of NPs influence the efficiency of team-based practice in Taiwan. To improve the team-based practice of NPs, healthcare administrators must support the practice autonomy of NPs.

Determining factors affecting job strain for nurse practitioners in acute care practice.

PURPOSE: To investigate nurse practitioners' (NPs) experience of job strain in acute care settings, and to examine the factors that may affect job strain in that context. DESIGN: Descriptive design using a national survey was employed. METHODS: A total of 1396 NPs completed online surveys that recorded demographic characteristics and included a Job Content Questionnaire (JCQ), a Condition for Work Effectiveness Questionnaire (CWEQ), and the Dempster Practice Behavior Scale (DPBS). Multiple logistic regressions were conducted to explore the factors associated with job strain types. FINDINGS: NPs were classified into job strain categories of passive (24.4%), active (31.4%), low (19.2%), or high (24.9%). The passive job strain type was associated with overtime hours, organizational empowerment, and autonomy. The active job type was associated with higher organizational empowerment and autonomy. The high-strain and low-strain job types were both associated with overtime hours and autonomy. CONCLUSION: Nearly 25% of acute care NPs are in a high job strain type. Organizational empowerment and autonomy were two major factors associated with the passive and active job strain types. Overtime hours and autonomy were both associated with the high-strain and low-strain job types. CLINICAL RELEVANCE: Supportive hospital/nursing leadership should acknowledge the impact of NP practice as they can contribute to the operational efficacy of their organization. Hospital administrators should provide a supportive practice environment by empowering NPs, enhancing autonomy, and addressing working conditions for NPs to decrease the odds of having a passive or high-strain job type in practice.

A pathway to negative acculturation: marital maladjustment mediates the relationship between the length of residency and depressive symptoms in immigrant women in Taiwan.

BACKGROUND: Immigrant women in Taiwan experience a variety of acculturative and marital problems that result in a mental-health problems. We examined the mediational effect of marital adjustment on the relationship between acculturation and depressive symptoms in immigrant women in Taiwan. METHODS: All participants (N = 127) were interviewed to collect data regarding their basic sociodemographics, depressive symptoms, acculturation (using language proficiency and years in Taiwan as indicators), and marital adjustment. We used a Sobel test to examine how marital adjustment mediates the relationship between acculturation and depressive symptoms. RESULTS: Our results indicated that an increased length of residency exacerbated depressive symptoms (ß = 0.62, p = 0.03) and that this relationship contributed, in part, to the mediational effect of marital adjustment. That is, marital adjustment deteriorated with the length of residency (ß = - 0.26, p = 0.0013), resulting in the development of depressive symptoms (ß = - 0.95, p = 0.0013). CONCLUSION: Although the duration of residency may be useful as a proxy for acculturation in the assessment of some health outcomes, our findings imply that it is better to conceptualize it as a cumulative stress when considering the mental health of immigrant women. Marital maladjustment acts as a mediator in this relationship. As such, it is important to provide immigrant families with programs and resources to assist them in adapting to their marriages and to improve the mental health of immigrant women.

Organizational empowerment and practice outcomes of acute care nurse practitioners in Taiwan: A national survey.

BACKGROUND: Nurse practitioners (NPs) play an important role in addressing growing health care needs. Among NPs, organizational empowerment is positively associated with overall practice outcomes. Therefore, efforts to promote organizational empowerment in practice are necessary to increase job satisfaction among NPs as well as decrease the stress and intention to leave. PURPOSE: This study investigated the relationships of organizational empowerment and practice outcomes of job satisfaction, work stress, and intention to leave in acute care practices. METHODOLOGICAL ORIENTATION: This study was conducted as a cross-sectional design with a national survey of 946 acute care NPs. Questionnaires contained demographic and practice characteristics, Misener Nurse Practitioner Job Satisfaction Scale, Condition for Work Effectiveness Questionnaire II, and the work stress VAS scale. Hierarchical Linear Model (HLM) was used to investigate individual NP-level or organization-level effects on job satisfaction. The factors associated with job satisfaction were examined by stepwise multiple regression. RESULTS: The organizational empowerment was low, work stress was moderately high, and job satisfaction was between slightly unsatisfied and slightly satisfied. The HLM results indicated that organization-level effects did not affect the job satisfaction of NPs. Nurse practitioners with greater formal power, resources, and informal power had higher job satisfaction. Conversely, NPs with an intention to leave and a higher level of stress showed lower job satisfaction. CONCLUSIONS: Organizational empowerment, intention to leave, and stress affect job satisfaction of acute care NPs in Taiwan. IMPLICATIONS FOR PRACTIC: To enhance the job satisfaction of NPs, health care administrators should empower NPs by providing access to opportunity, support, information, and resources in the health care delivery system.

The Impact of Organizational Support on Practice Outcomes in Nurse Practitioners in Taiwan.

BACKGROUND: Nurse practitioners (NPs) in Taiwan have practiced mainly in acute care hospitals since 2006. Although organizational support and level of support have been associated with the successful integration of NP roles and effective practice outcomes, organizational support in the context of NPs in inpatient settings is an area that has been rarely explored in the literature. PURPOSE: The purpose of this study was to investigate the relationship between organizational support and the practice outcomes of job satisfaction, care effectiveness, and intention to leave in NPs. METHODS: A national survey of 512 NPs was conducted that included a demographic characteristics datasheet, the Nurse Practitioner Primary Care Organizational Climate Questionnaire, the Misener Nurse Practitioner Job Satisfaction Scale, and the Nurse Practitioner Care Effectiveness Scale. Multiple regression analysis was applied to explore the specific factors associated with job satisfaction. The statistical significance level was set at .05 with a two-tailed test. All statistical analyses were conducted using SPSS Statistics Version 22.0 software. RESULTS: More than half of the participants were found to be dissatisfied with their hospital managers (54.8%) and with each dimension of organizational support. Overall, 82.1% of the participants were satisfied with their current practice. A multiple regression analysis showed that the participants who perceived higher levels of organizational support in the workplace (ß = .53, p < .001), expressed satisfaction with working with their managers (ß = .25, p < .001), or perceived better care outcomes (ß = .10, p < .001) reported higher job satisfaction. In addition, the participants who expressed intention to leave within 1 year (ß = -.09, p < .001) and those with higher patient loads (ß = -.09, p < .001) reported lower job satisfaction. Organizational support was found to explain 50% of the variance in job satisfaction. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: The results of this study highlight organizational support as the most important factor affecting job satisfaction in NPs. Therefore, administrators work to promote organizational support and improve the work environment to enhance the job satisfaction, increase the clinical practice retention, and improve the care outcomes of NPs.

Cancer pain and lower functional status predict poor trajectories of symptom and fatigue distress in patients with lung cancer.

OBJECTIVE: To identify distinct subgroups of patients newly diagnosed with lung cancer (LC) over time and to explore the predictors of distinct trajectories of symptom and fatigue distress in LC patients. METHODS: A total of 120 patients newly diagnosed with LC were recruited in this longitudinal prospective study. Our survey investigated patients' symptoms in 6 months. Latent growth curve analysis (LGCA) was conducted to identify patients with distinct trajectories of symptom and fatigue distress. The characteristics of the patients among groups were compared for statistical differences by the chi-square test or ANOVA. RESULTS: The results of LGCA revealed that the linear three-trajectory model had the best model fit for symptom and fatigue distress. Patients' symptom and fatigue distress improved with time, except for patients with increasing trajectories. Patients' trajectories of symptom and fatigue distress were affected by pain, lower functional status, total symptom score and depression. Moreover, patients with increasing trajectories of symptom and fatigue distress experienced more pain, physiological symptoms and depression from 1 to 6 months. CONCLUSIONS: Pain and functional status were the major factors that deteriorated the recovery of trajectory in symptom distress and fatigue distress among patients with increasing trajectories.

Smartphone education improves embarrassment, bowel preparation, and satisfaction with care in patients receiving colonoscopy: A randomized controlled trail.

BACKGROUND: Colonoscopy is considered a safe and effective tool for detecting colorectal cancer. Nevertheless, the proportion of patients are hesitating to receive colonoscopy. Smartphone education may decrease the barrier of colonoscopy. The aim of this study is to examine the effectiveness of smartphone education in colonoscopy. METHODS: We conducted a prospective, double-blinded, randomized, controlled study to examine the effectiveness of smartphone education on embarrassment, bowel preparation, and satisfaction in colonoscopy. The patients' embarrassment was measured by the colonoscopy embarrassment scale. The quality of the bowel preparation was evaluated by gastroenterologists according to the Aronchik Scale. The satisfaction of colonoscopy care was assessed by a satisfaction scale developed by the authors. RESULTS: A total of 150 patients were analyzed in the smartphone education and control groups (n = 75 in each group). The smartphone education group reported fewer embarrassment (B = -2.78, P = .02) than those of the control group, the patients who were older (B = .15, P = .001) and who were male (B = 2.91, P = .003) showed higher embarrassment. Additionally, smartphone education group were likely to have better colon preparation (odds ratio = 2.46, 95% confidence interval: 1.20-5.02) than that of the control group. Smartphone education also improved the satisfaction with care (ß = 4.60, P < .001), and above normal body mass index decreased the satisfaction with care (ß = -0.19, P < .05). CONCLUSION: Smartphone education improves embarrassment, bowel preparation, and satisfaction with care in patients receiving colonoscopy.

Factors related to the quality of life in liver cancer patients during treatment phase: A follow-up study.

OBJECTIVE: This study aims to explore the predictive value of demographic and clinical factors in changes in quality of life (QoL) in liver cancer (LC) patients over time. METHODS: We performed a prospective cohort study in 128 patients who had 4 time point data newly diagnosed with LC at two hospitals in Taiwan. Different functional QoL was measured by QLQ-C30. Specific characteristics were predictors for distinct functional QoL, estimated by a generalised estimating equation (GEE). RESULTS: Patients who received liver resection or radiofrequency ablation therapy (RFA) versus transarterial chemoembolisation (TACE) or transcatheter arterial embolisation (TAE) experienced a decrease in physical function from baseline to 1 month. In addition, patients who underwent liver resection versus RFA experienced a significant recovery in cognitive functioning from baseline to 6 months. Patients with advanced stage compared to those in early stage had a reduction in physical functioning from baseline to 1 month. The alcohol intake, hepatitis C infection and the job also affected the changes in physical and cognitive functioning. CONCLUSION: Healthcare professionals should pay attention to changes after treatment in the short term; additionally, they need to provide health education to modifiable factors such as alcohol intake attributed to the deterioration in QoL.

Predictors for lower urinary tract symptoms and the urinary specific quality of life in prostate cancer patients: One-year follow-up.

BACKGROUND: Prostate cancer (PCa) is the most frequently diagnosed cancer and is becoming a growing concern in global epidemiology. Quality of life of patients has become a major outcome for cancer care but limited study investigated quality of life of PCa patients. Our study is to investigate predictors for treatment outcomes of lower urinary tract symptoms (LUTS), nocturia, and the urinary specific quality of life (uQoL) in PCa patients one year following treatment. METHODS: A prospective study of 131 consecutive patients was conducted with outcome measurements before treatment, at 3 months, 6 months, and one year following therapy. We utilized the International Prostate Symptom Score questionnaire to collect data. Generalized estimating equations were performed to identify predictors for major outcomes of LUTS, nocturia, and uQoL. RESULTS: LUTS increased slightly over time, but nocturia and uQoL were improved from baseline to 12 months. Results of the interaction analysis indicated that patients with TNM stage 3 compared with those with stage 2 had a reduction in LUTS from diagnosis to 6 months. Patients who received surgery or radiation compared to hormone therapy had worse nocturia from diagnosis to 6 months compared to those of patients who received hormone therapy. Higher body mass index (BMI) decreased the uQoL from diagnosis to 3 months, and higher prostate-specific antigen (PSA) level deteriorated the uQoL from diagnosis to 12 months. CONCLUSION: TNM stage and BMI affected the LUTS. Patients undergone a prostatectomy or radiation therapy showed more frequency of nocturia, BMI and PSA were also risk factors for nocturia. Moreover, patients' age, BMI, and PSA affected uQoL. In such patients, we recommend close monitoring of patients' specific characteristics such as TNM stage, BMI, and PSA for a better quality of life.

Prognostic association of demographic and clinical factors with the change rates of symptoms and depression among patients with hepatocellular carcinoma.

PURPOSE: To identify the predictive value of demographic and clinical factors for determining changes in physical and depressive symptom among hepatocellular carcinoma (HCC) patients over time. METHODS: We performed a prospective cohort study of 128 patients newly diagnosed with HCC in Taiwan. Each patient had four time-point data after the follow-up. Patients' physical symptoms were evaluated with the Edmonton Symptom Assessment System (ESAS). Psychological symptoms were evaluated with the Hospital Anxiety and Depression Scale (HADS). Clinical factors and demographic characteristics were predictors of physical and psychological symptoms, as estimated by a generalized estimating equation (GEE). RESULTS: We found that patients who had a smoking habit and Barcelona Clinic Liver Cancer (BCLC) Stage B disease underwent radiofrequency ablation therapy (RFA) or liver resection, and those who had higher alanine aminotransferase (GPT) level reported more symptoms from baseline to 1 month. Symptoms increased from baseline to 3 months in elderly patients and patients with higher GPT levels. Additionally, patients who had jobs, underwent liver resection, and had BCLC Stage C disease had increased symptoms of depression from baseline to 1 month; in particular, BCLC Stage D disease had negative long-term effects on depression scores from baseline to four-time points following therapy. CONCLUSION: Advanced BCLC stage and undergoing RFA or liver resection were most closely associated with worsening physical and psychological symptoms over time. Clinical professionals should pay attention to these factors that affect physical and psychological symptoms during treatment.

Enhanced directly-observed treatment short-course for tuberculosis control program in mountain areas of Taiwan.

INTRODUCTION: Directly Observed Treatment Short course (DOTS) is one of the most cost-effective approaches for TB treatment. However, TB incidence rates remain high in the mountain areas of Taiwan. A lay health advisor (LHA) strategy is integrated into DOTS as an Enhanced-DOTS (E-DOTS) to provide trustworthy, culturally-specific services in mountain areas that consider the characteristics of local ethnic groups. METHODOLOGY: We recruited two Taiwanese indigenes as LHAs (one for each county) to screen close contacts in five townships of Hualien and Nantou counties from January 1, 2011 to December 31, 2013. Incidence and active finding rates of TB during the E-DOTS periods (2011-2013 for Hualien and 2012-2013 for Nantou) were compared with data when traditional DOTS was implemented (2006-2010 for Hualien and 2006-2011 for Nantou) to evaluate the effectiveness of E-DOTS using the before-and-after study design. RESULTS: Incidence rate in Hualien decreased from 393.3 in 2011 to 235.7 in 2013 per 100,000 population and from 338 in 2012 to 235.5 in 2013 in Nantou mountain area. Furthermore, the active case finding rate increased from 15.42% in 2012 to 27.38% in 2013 as compared to an average of 6.5% for CDC, Taiwan, for the specified years. TB treatment success rates were significantly improved from an average of less than 80% to an average of higher than 90% after E-DOTS was implemented. CONCLUSIONS: Our findings highlighted that the use of LHAs in E-DOTS is an effective and applicable strategy for controlling tuberculosis in the mountain areas of Taiwan.

Is There a Healthy Immigrant Effect Among Women Through Transnational Marriage? Results from Immigrant Women from Southeast Asian Countries in Taiwan.

In this study we examine whether there is healthy immigrant effect among women immigrated to Taiwan through transnational marriage. A sample of immigrant women (N = 246) with original nativity of Southeast Asian countries and Taiwanese-born women sample (N = 201) was recruited from December 2008 to December 2009. Their depressive symptoms, acculturative stresses and family functioning were assessed by a series of questionnaires. Immigrant women had lower depressive scores than their native-born counterparts when other potential confounders were controlled for in the multiple regression model. Our findings suggest that the healthy immigrant effect exists among immigrant women in Taiwan. Although such effect may due to immigrant women is a highly selective population with hardy mental characteristics, it is crucial to improve immigrant women's mental health by helping them to enhance the ability of expressing emotions between family members as well as by mitigating socioeconomic inequality of cross-cultural immigrant families.

Perceived discrimination, family functioning, and depressive symptoms among immigrant women in Taiwan.

This study examined the moderating effect of family functioning on the relationship between perceived discrimination and depressive symptoms in immigrant women. A total of 239 immigrant women were selected from four administrative regions in Central Taiwan. Questionnaires concerning perceived discrimination, family functioning (including family cohesion and family adaptability), depressive symptoms, and demographic characteristics were completed by either women themselves (N = 120) or their husbands (N = 119). The moderating effect of family functioning on the relationship between perceived discrimination and depression symptoms was analyzed using multiple regression analysis. Findings showed that a higher level of perceived discrimination among immigrant women is associated with more severe depressive symptoms. Family functioning serves as a moderator between the relationship of perceived discrimination and depressive symptoms, but the moderating effect of family adaptability was evident only in data reported by immigrant women. The results indicate that perceived discrimination has negative mental health implications, and also point to the importance of family functioning for depression. Findings suggest that providers should consider addressing immigrant women's mental health needs through declining their psychosocial distress at multiple ecological levels.