Melody Hertzog

Considerations in determining sample size for pilot studies

There is little published guidance concerning how large a pilot study should be. General guidelines, for example using 10% of the sample required for a full study, may be inadequate for aims such as assessment of the adequacy of instrumentation or providing statistical estimates for a larger study. This article illustrates how confidence intervals constructed around a desired or anticipated value can help determine the sample size needed. Samples ranging in size from 10 to 40 per group are evaluated for their adequacy in providing estimates precise enough to meet a variety of possible aims. General sample size guidelines by type of aim are offered.

Sedative music reduces anxiety and pain during chair rest after open-heart surgery

Abstract Open‐heart surgery patients report anxiety and pain with chair rest despite opioid analgesic use. The effectiveness of non‐pharmacological complementary methods (sedative music and scheduled rest) in reducing anxiety and pain during chair rest was tested using a three‐group pretest–posttest experimental design with 61 adult postoperative open‐heart surgery patients. Patients were randomly assigned to receive 30 min of sedative music (N=19), scheduled rest (N=21), or treatment as usual (N=21) during chair rest. Anxiety, pain sensation, and pain distress were measured with visual analogue scales at chair rest initiation and 30 min later. Repeated measures MANOVA indicated significant group differences in anxiety, pain sensation, and pain distress from pretest to posttest, P<0.001. Univariate repeated measures ANOVA (P≤0.001) and post hoc dependent t‐tests indicated that in the sedative music and scheduled rest groups, anxiety, pain sensation, and pain distress all decreased significantly, P<0.001–0.015; while in the treatment as usual group, no significant differences occurred. Further, independent t‐tests indicated significantly less posttest anxiety, pain sensation, and pain distress in the sedative music group than in the scheduled rest or treatment as usual groups (P<0.001–0.006). Thus, in this randomized control trial, sedative music was more effective than scheduled rest and treatment as usual in decreasing anxiety and pain in open‐heart surgery patients during first time chair rest. Patients should be encouraged to use sedative music as an adjuvant to medication during chair rest.

The effects of exercise training on fatigue and dyspnea in heart failure.

Background: Physiological benefits of exercise training for heart failure (HF) patients have been demonstrated, however little is known about the effects of training on the symptoms of fatigue and dyspnea. Aim: The purpose of this study was to examine HF symptoms of fatigue and dyspnea in response to a 24-week exercise training intervention. Methods: This pilot study was a randomized, two-group repeated measures design. Fifteen subjects in the intervention group completed a combination of aerobic and resistance training three times per week in a standard cardiac rehabilitation setting. The control group consisted of 6 subjects who were instructed not to begin any formal exercise program during the 24-week intervention. Results: Subjects (19 males and 2 females) had a mean age of 66.2 ± 10.2 years and mean ejection fraction (EF) of 28.4 ± 7.4%. Non-parametric Friedman Analysis of Variance by Ranks showed the exercise group significantly decreased sensory fatigue (Piper Fatigue Scale) over time (χ 2 = 6.49, p = .04) while the control group did not change (χ 2 = 0.93, p = .63). Dyspnea showed a non-significant decrease over time for the exercise group (χ 2 = 4.16, p = .13) while the control group showed a decrease from baseline to 12 weeks but an increase to above baseline values by week 24 (χ 2 = 0.18, p = .91). Conclusion: These results provide support for the beneficial effects of exercise training on symptoms of fatigue and dyspnea in HF patients. Larger studies to evaluate symptom response to exercise are needed.

Influence of intention and self-efficacy levels on duration of breastfeeding for midwest rural mothers

OBJECTIVES The purpose of this study was to explore the relationship of two modifiable factors (intention to breastfeed for 6 months and breastfeeding self-efficacy) with the duration of breastfeeding in primiparous women. FINDINGS Analyzed by logistic regression in a single prediction model, stronger intention (odds ratio = 1.89) and higher levels of self-efficacy at 2 weeks postpartum (odds ratio = 1.04) were significantly (p < .05) associated with an increased probability of breastfeeding for 6 months. CONCLUSIONS The combined influence of higher intention and self-efficacy increased the likelihood of breastfeeding for the recommended 6 months. Interventions to reinforce both should be designed and evaluated.

Determinants of Older Rural Women’s Activity and Eating

This research examined the relationship of cognitive-perceptual determinants from the Health Promotion Model to physical activity and healthy eating at baseline of a clinical trial among rural women aged 50 to 69. Two multivariate regression analyses with canonical correlation (N = 179) each yielded one interpretable canonical variate that explained similar amounts of variance (21.7% and 22.5%) in sets of activity and eating variables. In both analyses, the determinants set is a linear combination of all four cognitive-perceptual constructs from the model (perceived self-efficacy, benefits, barriers, interpersonal influences). The activity behavior set included caloric expenditure, VO2max, and stretching and strengthening activity, whereas the eating behavior set included daily percentage of calories from fat and servings of fruits and vegetables, meat, and whole grains. As predicted by theory, greater self-efficacy, benefits and interpersonal support, and fewer barriers are associated with desirable healthy lifestyle behaviors.

Clinical trial of tailored activity and eating newsletters with older rural women

Background: Unhealthy diet and lack of physical activity increase rural midlife and older womens risk of chronic diseases and premature death, and they are behind urban residents in meeting Healthy People 2010 objectives. Objectives: The objective of this study was to compare a tailored intervention based on the Health Promotion Model with a generic intervention to increase physical activity and healthy eating among rural women. Methods: In a randomized-by-site, community-based, controlled, clinical trial, Wellness for Women, 225 women aged 50 to 69 years were recruited in two similar rural areas. Over 12 months, women received by mail either 18 generic newsletters or 18 newsletters computer tailored on Health Promotion Model behavior-specific cognitions (benefits, barriers, self-efficacy, and interpersonal support), activity, and eating. Outcomes at 6 and 12 months included behavioral markers and biomarkers of physical activity and eating. Data were analyzed by repeated-measures analysis of variance and chi-square tests (&agr; < .05). Results: Both groups significantly increased stretching and strengthening exercise and fruit and vegetable servings and decreased percentage of calories from fat, whereas only the tailored group increased moderate or greater intensity activity and decreased percentage of calories from saturated fat from baseline to 6 months. Both groups increased stretching and strengthening exercise, whereas only the tailored group increased moderate or greater intensity activity and fruit and vegetable servings and decreased percentage of calories from fat from baseline to 12 months. Both groups had several changes in biomarkers over the study. A higher proportion of women receiving tailored newsletters met Healthy People 2010 criteria for moderate or greater intensity activity, fruit and vegetable servings, and percentage of calories from fat at 12 months. Discussion: Mailed computer-tailored and generic print newsletters facilitated the adoption of change in both activity and eating over 6 months. Tailored newsletters were more efficacious in facilitating change over 12 months.

Effects of a Physical Activity Intervention for Women

Physical activity is associated with health and reduced mortality risk, yet only15% ofU.S. adults achieve adequate activity. This study is an experimental repeated measures nested design randomizing two similar rural communities to investigate the effectiveness of the Heart and Soul Physical Activity Program (HSPAP) (Peterson, 2002) in promoting physical activity in midlife women (n =42) aged 35 to 65 years. The HSPAP, an innovative church-based health promotion intervention, is conceptualized in social support and designed to increase physical activity, energy expenditure (EE), and cardiorespiratory fitness (VO2 max), measured over time. A significant interaction (p < .001) was found for EE in one HSPAP group increasing their EE by 1,010 kcals/week. HSPAP participants increased their VO2 max level by 75% (p < .001) and 10%; comparison groups stayed the same or declined 16%. Study results provide preliminary support for the HSPAP intervention as an effective treatment to improve physical activity levels in sedentary, rural, midlife women.

Pilot Testing of a Medication Self-Management Transition Intervention for Heart Failure Patients

This pilot study examined the impact of a hospital transition intervention for older adults (≥ 65 years of age) with heart failure (HF) to promote medication use self-management. Forty subjects, hospitalized with either primary or secondary HF, had a mean age of 76.9 ± 6.5 years; 65% were males. The majority of subjects (55%) had NYHA Class III HF. A prospective, repeated measures experimental design was used. Baseline and follow-up data (1- and 3-months after hospitalization) were obtained using the Medication Regimen Complexity Index, Brief Medication Questionnaire, Drug Regiment Unassisted Grading Scale, and Kansas City Cardiomyopathy Questionnaire. Using repeated measures analysis of covariance (ANCOVA), with baseline measures as covariates, the transition intervention group had higher levels of medication adherence (F(1,35) = 13.4, p < .001), self-efficacy for HF self-care (F(1,35) = 17.9, p < .001) and had significantly fewer HF related symptoms that impaired health related quality of life (F(1,35) = 9.1, p = .006).

A brief neuropsychological battery for use in the chronic heart failure population.

Background: Cognitive impairment is a recognized consequence of heart failure; however, there are no neuropsychological batteries with documented psychometric data in the chronic heart failure population. Aims: To document the psychometric properties of a brief neuropsychological battery in a chronic heart failure sample. Methods: The Repeatable Battery for the Assessment of Neuropsychological Status, Trail Making Test Part A and Part B, and letter fluency was administered to a sample of individuals with chronic heart failure. Results: Eighty individuals with stable heart failure participated in this study. Individuals with chronic heart failure scored significantly lower than expected age and education adjusted norms in the domains of attention (p < 0.001), memory (p < 0.001), language (p < 0.001), executive function (p < 0.001), and psychomotor speed (p = 0.02). Scores on the tests of memory and executive function correlated to functional status (r = 0.28, p = 0.02 and r = 0.29, p = 0.03, respectively). Acceptable convergent validity and test–retest reliability were documented for this battery. Conclusion: The neuropsychological battery had adequate reliability and validity in individuals with chronic heart failure.

Usual and worst symptom severity and interference with function in breast cancer survivors.

BACKGROUND Breast cancer survivors receive routine medical follow-up but are screened less frequently to detect symptom severity and interference with function in daily life. OBJECTIVES Among breast cancer survivors, we describe the usual and worst severity of 5 common symptoms and the extent to which these symptoms interfere with general activity and enjoyment of life, we determine the associations among symptoms and the interference items, and we explore associations of interference with function and the most prevalent symptoms. METHODS The cross-sectional, descriptive 1-page Breast Cancer Survivor Symptom Survey was mailed to breast cancer survivors identified in a clinical database (ONCOBASE). In total, 184/457 (40.3%) surveys were returned and 162 (35.4%) were used. Participants recorded usual and worst severity of 5 symptoms (fatigue, disturbed sleep, pain, distress, and numbness/tingling) and symptom interference with general activity and enjoyment of life during the past 7 days. RESULTS Participants reported usual symptom severity as mild and highest for sleep disturbance, followed by fatigue, distress, numbness/tingling, and pain. Participants recorded worst sleep disturbance and fatigue as moderately severe. Higher pain and fatigue were associated with all other symptoms, whereas disturbed sleep and distress were related to all except numbness/tingling. All symptoms interfered with general activity and enjoyment of life. Pain and numbness/tingling were associated with lower function and disturbed sleep, and made a unique contribution to fatigue. LIMITATIONS Limitations of the study include relatively low response and use of a modification of an established scale. CONCLUSION Symptoms often coexisted and contributed to interference with daily function. Pain was most consistently associated with interference with function and severity of other symptoms.