Impact of shift work on the diurnal cortisol rhythm: a one-year longitudinal study in junior physicians

Background

Cumulative epidemiological evidence suggests that shift work exerts harmful effects on human health. However, the physiological mechanisms are not well understood. This study aimed to examine the impact of shift work on the dysregulation of the hypothalamic-pituitary-adrenal axis, i.e. diurnal cortisol rhythm.

Methods

Seventy physicians with a mean age 30 years participated in this one-year longitudinal study. Working schedules, either shift work or regular schedules with day shift, were assessed at baseline. Salivary cortisol samples were collected on two consecutive regular working days, four times a day (including waking, +?4 h, +?8 h, and?+?16 h), at both baseline and the one-year follow-up. The diurnal cortisol decline (slope) and total cortisol concentration (area under the curve, AUC) were calculated.

Results

After adjusting for cortisol secretion at baseline and numerous covariates, shift work at baseline significantly predicted a steeper slope (p?<?0.01) and a larger AUC (p?<?0.05) of diurnal cortisol rhythm at follow-up in this sample of physicians. In particular, waking cortisol at follow-up was significantly higher among those engaged in shift work than day shift (p?<?0.01).

Conclusions

Our findings support the notion that shift work changes the diurnal cortisol pattern, and is predictive of increased cortisol secretion consequently in junior physicians.

     

Using Electronic Health Record Alerts to Increase Safety Planning with Youth At-Risk for Suicide: A Non-randomized Trial

Background

No study to date has examined the effectiveness of integrating clinical decision support tools, like electronic health record (EHR) alerts, into the clinical care of youth at-risk for suicide.

Objective

This study aimed to examine the feasibility and acceptability of using an EHR alert to increase clinicians’ use of safety planning with youth at-risk for suicide in an outpatient pediatric psychiatry clinic serving an urban low-income Latino community.

Methods

An alert intervention was developed to remind clinicians to complete a safety plan whenever they documented that their patient endorsed suicidal ideation, plan, or attempt during a visit in EHR notes. The alert appeared as a separate window containing a reminder message to complete a safety plan once a clinician finished visit documentation.

Results

There were 69 at-risk patients between the ages of 13–21 in the intervention period (M = 15.71; SD = 1.86; 66.7% female) and 64 (M = 15.38; SD = 1.93; 68.6% female) in the control period. Logistic regression analyses indicated that patients in the intervention period were significantly more likely than patients in the control period to receive a safety plan (p < .01). The pattern of results remained the same after adjusting for demographic variables (p = .01). Forty clinicians also completed a questionnaire assessing their satisfaction with the EHR alert, indicating moderate satisfaction (M = 3.01; SD = 0.63; range = 1.11–4.11).

Conclusions

EHR alerts are associated with changes in clinicians’ behavior and improved compliance with best clinical practices for at-risk youth.

     

The role of mindfulness in distress and quality of life for men with advanced prostate cancer

Objective

To examine the extent to which mindfulness skills influence psychological distress and health-related quality of life (HRQOL) in men with metastatic or castration-resistant biochemical progression of prostate cancer.

Patients and methods

A cross-sectional survey of 190 men (46 % response; mean age 71 years, SD = 8.7, range 40–91 years) with advanced prostate cancer, assessed psychological and cancer-specific distress, HRQOL. Mindfulness skills were assessed as potential predictors of adjustment outcomes.

Results

Overall, 39 % of men reported high psychological distress. One third had accessed psychological support previously although only 10 % were under current psychological care. One quarter had accessed a prostate cancer support group in the past six months.Higher HRQOL and lower cancer-specific and global psychological distress were related to non-judging of inner experience (p < 0.001).Higher HRQOL and lower psychological distress were related to acting with awareness (p < 0.001). Lower distress was also related to higher non-reactivity to inner experience and a lower level of observing (p < 0.05).

Conclusions

Men with advanced prostate cancer are at risk of poor psychological outcomes. Psychological flexibility may be a promising target for interventions to improve adjustment outcomes in this patient group.

Clinical Trial Registry

Trial Registration: ACTRN12612000306819

     

Evaluation of bone mineral density and 25-hydroxyvitamin D levels in subjects with silica exposure

Objective

The purpose of the study was to evaluate the bone mineral density (BMD) and 25-hydroxyvitamin D (25(OH)D) levels in patients with silica exposure.

Materials and methods

The study included 104 male subjects with silica exposure and 36 healthy subjects. Posterior–anterior radiographs were classified according to the International Labour Office (ILO) Classification. Category 0 patients were classified as Group I (n = 54), category I patients were classified as Group II (n = 25), Category II and III patients were classified as Group III (n = 25).

Results

Femoral neck BMD values were significantly lower in Group III (p = 0.007). Lumbar vertebrae BMD values were significantly lower in all groups with silica exposure than in the control group (p = 0.000). The osteoporosis rate was significantly higher in Group III (p = 0.000). Subjects with silica exposure were determined to have diminished 25(OH)D levels (p = 0.012).

Conclusion

The results of this study demonstrated that subjects with silica exposure have diminished BMD and 25(OH)D levels.

     

Sustained quality of life improvement after intracoronary injection of autologous bone marrow cells in the setting of acute myocardial infarction: results from the BONAMI trial

Purpose

Cardiac cell therapy is a promising treatment for acute myocardial infarction (AMI), leading to cardiac function improvement. However, whether it translates into quality of life (QoL) improvement is unclear. We hypothesized that administration of bone marrow cells (BMC) to patients with AMI improves QoL.

Methods

In the multicenter BONAMI trial (NCT00200707), patients with reperfused AMI and decreased myocardial viability were randomized to intracoronary autologous BMC infusion (n = 52) or state-of-the-art therapy (n = 49). QoL data, derived from the Minnesota Living with Heart Failure questionnaire (MLHFQ), were obtained 1, 3, and 12 months after AMI and analyzed using a Rasch-family model.

Results

Using this model, QoL improved over time in the BMC group (p = 0.025) but not in the control group. Furthermore, the BMC-group patients displayed a better QoL than the control-group patients at 3 and 12 months post-AMI (p = 0.034 and p = 0.003, respectively). These findings were not detected when analyzing MLHFQ data using a standard method. Cardiac function, myocardial viability, mortality, and number of major adverse cardiac events did not differ between treatment groups.

Conclusion

Our results suggest that BMC therapy can improve QoL, stressing the need for confirmation trials and for systematic QoL assessment in cardiac cell therapy trials .

     

Adaptation and validation of the “tolerability and quality of life” (TOOL) questionnaire in Chinese bipolar patients

Background

It is well known that the antipsychotic drugs impact the health-related quality of life (HRQoL) of the bipolar patients. The side effects had been assessed only from the doctors’ perspective and neglected the patients’ subjective feeling. The aim of the study is to validate the specific instrument “tolerability and quality of life” (TOOL) into Chinese to describe and grade the impact of antipsychotic drugs on HRQoL from patients’ view.

Methods

A psychometric study was conducted with euthymic bipolar disorder patients (N = 105) under antipsychotic treatment. The psychometric properties of the TOOL, including internal consistency, retest reliability, concurrent validity, content validity, discriminative validity, item analysis, confirmatory factor analysis and feasibility, were analyzed.

Results

The internal consistency and intraclass correlation coefficient (ICC) were adequate (Cronbach’s alpha = 0.80 and ICC = 0.81). A confirmatory factor analysis (CFA) validated the one-factor model. Significant Spearman’s rank correlations between the TOOL and both Bref QoL.BD (Brief version of Quality of Life in Bipolar Disorder) (r = ?0.33, P < 0.01) and UKU (Udvalg for Kliniske Undersogelser side effects scale) (r = 0.13, P < 0.05) were found.

Limitations

Small sample size and no specific self-report instrument in Chinese to evaluate the criterion validity.

Conclusions

TOOL appears to be a reliable and valid measure to assess the impact of adverse events of antipsychotic drugs on HRQoL from the patients’ perspective.

     

Cost and Budget Impact Analysis of an Accurate Intraoperative Sentinel Lymph Node Diagnosis for Breast Cancer Metastasis

Background

Conventional intraoperative sentinel lymph node biopsy (SLNB) in breast cancer (BC) has limitations in establishing a definitive diagnosis of metastasis intraoperatively, leading to an unnecessary second operation. The one-step nucleic amplification assay (OSNA) provides accurate intraoperative diagnosis and avoids further testing. Only five articles have researched the cost and cost effectiveness of this diagnostic tool, although many hospitals have adopted it, and economic evaluation is needed for budget holders.

Objective

We aimed to measure the budget impact in Japanese BC patients after the introduction of OSNA, and assess the certainty of the results.

Methods

Budget impact analysis of OSNA on Japanese healthcare expenditure from 2015 to 2020. Local governments, society-managed health insurers, and Japan health insurance associations were the budget holders. In order to assess the cost gap between the gold standard (GS) and OSNA in intraoperative SLNB, a two-scenario comparative model that was structured using the clinical pathway of a BC patient group who received SLNB was applied. Clinical practice guidelines for BC were cited for cost estimation.

Results

The total estimated cost of all BC patients diagnosed by GS was US$1,023,313,850. The budget impact of OSNA in total health expenditure was ?US$24,413,153 (?US$346 per patient). Two-way sensitivity analysis between survival rate (SR) of the GS and OSNA was performed by illustrating a cost-saving threshold: y ? 1.14x ? 0.16 in positive patients, and y ? 0.96x + 0.029 in negative patients (x = SR–GS, y = SR–OSNA). Base inputs of the variables in these formulas demonstrated a cost saving.

Conclusion

OSNA reduces healthcare costs, as confirmed by sensitivity analysis.

     

Health-related quality of life in multiple sclerosis: role of cognitive appraisals of self,illness and treatment

Purpose

Health-related quality of life (HRQoL) is considered an important measure of treatment and rehabilitation outcomes in multiple sclerosis (MS) patients. In this study, we used multivariate regression analysis to examine the role of cognitive appraisals, adjusted for clinical, socioeconomic and demographic variables, as correlates of HRQoL in MS.

Methods

The cross-sectional study included 257 MS patients, who completed Multiple Sclerosis Impact Scale, Generalized Self-Efficacy Scale, Rosenberg Self-Esteem Scale, Brief Illness Perception Questionnaire, Treatment Beliefs Scale, Actually Received Support Scale (a part of Berlin Social Support Scale) and Socioeconomic Resources Scale. Demographic and clinical characteristics of the participants were collected with a self-report survey. Correlation and regression analyses were conducted to determine associations between the variables.

Results

Five variables, illness identity (β = 0.29, p ≤ 0.001), self-esteem (β = ?0.22, p ≤ 0.001), general self-efficacy (β = ?0.21, p ≤ 0.001), disability subgroup “EDSS” (β = 0.14, p = 0.006) and age (β = 0.12, p = 0.012), were significant correlates of HRQoL in MS. These variables explained 46 % of variance in the dependent variable. Moreover, we identified correlates of physical and psychological dimensions of HRQoL.

Conclusions

Cognitive appraisals, such as general self-efficacy, self-esteem and illness perception, are more salient correlates of HRQoL than social support, socioeconomic resources and clinical characteristics, such as type and duration of MS. Therefore, interventions aimed at cognitive appraisals may also improve HRQoL of MS patients.

     

The association between maternal nutrition and lifestyle during pregnancy and 2-year-old offspring adiposity: analysis from the ROLO study

Aim

To examine the association between maternal nutrition and lifestyle factors and offspring adiposity, using baseline and 2-year postpartum follow-up data from a randomised control trial of low glycaemic index diet.

Subject and methods

Food diaries and lifestyle questionnaires were completed during pregnancy and infant feeding and maternal lifestyle questionnaires 2 years postpartum for 281 mother and infant pairs from the ROLO study. Maternal anthropometry was measured throughout pregnancy and infant and maternal anthropometry was measured 2 years postpartum.

Results

Maternal 2 year postpartum body mass index (BMI) was positively associated with offspring BMI-for-age z-score (B?=?0.105, p?=?0.015). Trimester 2 saturated fat intake was positively associated with offspring subscapular:triceps skinfold ratio (B?=?0.018, p?=?0.001). Trimester 1 glycaemic index was also positively associated with offspring sum of subscapular and triceps skinfolds (B?=?0.009, p?=?0.029).

Conclusions

Maternal BMI 2 years postpartum was positively associated with offspring BMI. Pregnancy saturated fat intake was positively and polyunsaturated fat negatively associated with offspring adiposity. While further research is necessary, pregnancy and the postpartum period may be early opportunities to combat childhood obesity.

     

The relationship between dioxins and salivary steroid hormones in Vietnamese primiparae

Objective

Nearly 40 years after Agent Orange was last sprayed, we conducted a cross-sectional study to evaluate the impact of dioxin exposure on salivary hormones in Vietnamese primiparae. Our previous studies found higher levels of salivary cortisol and cortisone in one of the most highly dioxin-contaminated areas, known as a “hot-spot”, than in a non-exposed area. As a result, we suggested that further research with a larger number of participants would be needed to confirm whether dioxin affects steroid hormone levels in Vietnamese primiparae.

Methods

The concentration of steroid hormones in saliva was determined by liquid chromatography (electrospray ionization tandem mass spectrometry), whereas the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in breast milk were determined by gas chromatography-high resolution mass spectrometry, for a sample of the population from a “hot-spot” (n = 16) and a non-exposed area (n = 10). All subjects were aged between 20 and 30 years and had children aged between 4 and 16 weeks.

Results

The mean toxic equivalence of PCDDs, PCDFs and PCDDs + PCDFs in breast milk in the hot-spot area was found to be significantly higher than in the non-exposed area (p < 0.001). Likewise, salivary cortisol, cortisone and dehydroepiandrosterone (DHEA) levels were significantly higher in the hotspot area than in the non-exposed area (p < 0.05). As a result, herein we report, for the first time, that salivary DHEA levels in primiparae are higher in a hot-spot than in a non-exposed area, and that this may be the result of dioxin exposure.

Conclusions

Our findings highlight the long-term effects of Agent Orange/dioxin on steroid hormones in Vietnamese primiparae in the post-war period.

     

Iodine intake by adult residents of a farming area in Iwate Prefecture,Japan, and the accuracy of estimated iodine intake calculated using the Standard Tables of Food Composition in Japan

Objectives

Iodine intake by adults in farming districts in Northeastern Japan was evaluated by two methods: (1) government-approved food composition tables based calculation and (2) instrumental measurement. The correlation between these two values and a regression model for the calibration of calculated values was presented.

Methods

Iodine intake was calculated, using the values in the Japan Standard Tables of Food Composition (FCT), through the analysis of duplicate samples of complete 24-h food consumption for 90 adult subjects. In cases where the value for iodine content was not available in the FCT, it was assumed to be zero for that food item (calculated values). Iodine content was also measured by ICP-MS (measured values).

Results

Calculated and measured values rendered geometric means (GM) of 336 and 279 μg/day, respectively. There was no statistically significant (p > 0.05) difference between calculated and measured values. The correlation coefficient was 0.646 (p < 0.05).

Discussion

With this high correlation coefficient, a simple regression line can be applied to estimate measured value from calculated value. A survey of the literature suggests that the values in this study were similar to values that have been reported to date for Japan, and higher than those for other countries in Asia.

Conclusions

Iodine intake of Japanese adults was 336 μg/day (GM, calculated) and 279 μg/day (GM, measured). Both values correlated so well, with a correlation coefficient of 0.646, that a regression model (Y = 130.8 + 1.9479X, where X and Y are measured and calculated values, respectively) could be used to calibrate calculated values.

     

Are the Clinical Characteristics of Anxious Youths Participating in Non-treatment-Related Research Comparable to those of Youths Receiving Treatment?

Background

A key element of the evidence-based assessment and treatment movements is ensuring an adequate representation of clients across the different settings in which they receive mental health care (e.g., research and routine or usual care settings). Prior work has focused on comparing clients from research settings to those from usual care settings on various indices of clinical severity, impairment, and symptom levels.

Objective

In this study, we focused on examining clients from different types of research studies not only on levels of clinical severity, impairment, and symptoms, but also on the relations among these domains.

Methods

We addressed our objective in a sample of 73 youths meeting primary diagnostic criteria for generalized anxiety disorder (GAD); n = 32 were recruited specifically for a treatment study or received services from a university-based clinic (Youths Receiving Treatment; YRT), and n = 41 were recruited for a non-treatment assessment study (Non-Treatment Research Youths; NTRY).

Results

Relative to NTRY, YRT displayed greater GAD clinical severity, and higher generalized anxiety and worry levels. However, we observed no differences between groups in relations among measures of GAD clinical severity, generalized anxiety, and worry.

Conclusions

These findings have important implications for evidence-based practice and interpreting studies seeking to compare clients from research and clinical settings on clinical characteristics.

     

Age- and gender-specific associations between insomnia and falls in Boston Puerto Rican adults

Purpose

This study evaluated the age- and gender-specific associations between insomnia and falls in community-dwelling Puerto Rican adults, independently of multiple covariates.

Methods

Cross-sectional data were collected from 954 Puerto Ricans, aged 46–79 years, in Boston, Massachusetts. In-person interviews were conducted to collect information on sociodemographics and lifestyle, mental status, medication use, comorbidities, sleep duration, insomnia symptoms, and falls and fractures. Blood and urine samples, and bone density measures were collected to assess C-reactive protein, serum interleukin-6, urinary cortisol, and bone mineral density.

Results

Multivariate robust Poisson regressions suggested that adults with insomnia had a 32 % increased likelihood of having falls (PR 1.32, p < 0.05), after adjustment for multiple covariates. Age and gender modified the effect of insomnia on risk of falls. Insomnia was significantly associated with higher risk of falls in adults of 60 years or older (PR 1.49, p < 0.05) and in women (PR 1.36, p < 0.05), but not in adults younger than 60 years or in men. Insomnia was not associated with recurrent falls or fractures.

Conclusions

Age and gender need to be taken into account when considering treatment of insomnia in preventing geriatric falls. Well-designed evidence-based interventions to treat insomnia and improve sleep quality may reduce the risk of falls in this population.

     

Profiles of Emergent Writing Skills Among Preschool Children

Background

Research suggests that considerable individual differences may exist among preschool children in terms of emergent writing performance. However, there is no study examining this variability.

Objective

This research explored the patterns of within-group individual differences in the emergent writing skills of preschool children.

Method

Cluster analysis was employed to identify profiles of emergent writing skills in two independent samples (children from middle-socioeconomic status backgrounds N = 36; children from socioeconomically and racial/ethnically diverse backgrounds N = 367).

Results

Cluster analysis identified three emergent writing profiles: (1) highest emergent writing-strength in letter writing and spelling; (2) average emergent writing-strength in name writing; and (3) lowest emergent writing across skills. Children’s letter name knowledge and phonological awareness significantly predicted profile membership when controlling for age.

Conclusion

These findings provide evidence regarding the heterogeneity of preschool children’s emergent writing skills and suggest that different profiles of emergent writing can be explained by children’s letter name knowledge, phonological awareness, and age.

     

Assessment of the psychological burden associated with pruritus in hemodialysis patients using the kidney disease quality of life short form

Purpose

To assess whether depression symptoms, poor sleep and dry skin bother explain association between pruritus and the burden of kidney disease in maintenance hemodialysis (MHD) patients.

Methods

Cross-sectional study of 980 patients from a prospective study in dialysis units of Salvador, Brazil (PROHEMO). The Kidney Disease Quality of Life Short Form was used to determine scores of kidney disease burden (KDB) and sleep with higher scores indicating lower perceived burden and better sleep quality, respectively. The Center for Epidemiological Studies Depression Scale was used for depression symptoms.

Results

Prevalence of severe pruritus (very much or extreme) was 19.4%. Significantly (P < 0.001) lower mean KDB score by 11.44 points was observed for patients with severe pruritus (34.18 ± 27.51) than for those with no pruritus (45.62 ± 30.73). Severe pruritus was associated with poorer sleep quality, higher odds of dry skin bother and higher depression symptoms score. Association of pruritus with KDB score was virtually eliminated after adjustment for sleep, dry skin bother and depression symptoms.

Conclusions

This study shows strong associations of severe pruritus with higher depression symptoms, poorer sleep and dry skin bother among MHD patients. The results support special attention to MHD patients with pruritus who often face high psychological burden.

     

Is It Safe? Reliability and Validity of Structured Versus Unstructured Child Safety Judgments

Background

The LIRIK, an instrument for the assessment of child safety and risk, is designed to improve assessments by guiding professionals through a structured evaluation of relevant signs, risk factors, and protective factors.

Objective

We aimed to assess the interrater agreement and the predictive validity of professionals’ judgments made with the LIRIK in comparison to unstructured judgments.

Method

In study 1, professionals made safety and risk judgments for 12 vignettes with the LIRIK (group 1, n = 36) or without an instrument (group 2, n = 43). In study 2, we compared professionals’ safety and risk judgments for 370 children made with the LIRIK (group 1, n = 278) or with no instrument (group 2, n = 92), with outcomes indicating actual unsafety in files 6 months later.

Results

In study 1, agreement about safety and risks was poor to moderate in both groups. Differences between groups were small and inconsistent. In study 2, the predictive validity of judgments was weak to moderate in both groups. In neither group had unsafe outcomes increased consistently when unsafety or risks were assessed as higher.

Conclusions

Judgments made with the LIRIK were not more reliable or valid than unstructured professional judgments. These findings raise important questions about the value of risk assessment instruments and about how professional safety and risk judgments can be improved.

     

<Emphasis Type="Italic">Enterococcus hirae</Emphasis> biofilm formation on hospital material surfaces and effect of new biocides

Background

Nowadays, the bacterial contamination in the hospital environment is of particular concern because the hospital-acquired infections (HAIs), also known as nosocomial infections, are responsible for significant morbidity and mortality. This work evaluated the capability of Enterococcus hirae to form biofilm on different surfaces and the action of two biocides on the produced biofilms.

Methods

The biofilm formation of E. hirae ATCC 10541 was studied on polystyrene and stainless steel surfaces through the biomass quantification and the cell viability at 20 and 37 °C. The effect of LH IDROXI FAST and LH ENZYCLEAN SPRAY biocides on biomasses was expressed as percentage of biofilm reduction. E. hirae at 20 and 37 °C produced more biofilm on the stainless steel in respect to the polystyrene surface. The amount of viable cells was greater at 20 °C than with 37 °C on the two analyzed surfaces. Biocides revealed a good anti-biofilm activity with the most effect for LH ENZYCLEAN SPRAY on polystyrene and stainless steel at 37 °C with a maximum biofilm reduction of 85.72 and 86.37%, respectively.

Results

E. hirae is a moderate biofilm producer depending on surface material and temperature, and the analyzed biocides express a remarkable antibiofilm action.

Conclusion

The capability of E. hirae to form biofilm can be associated with its increasing incidence in hospital-acquired infections, and the adoption of suitable disinfectants is strongly recommended.

     

Correlates of health-related quality of life in young-old and old–old community-dwelling older adults

Purpose

This study aimed (1) to examine the role of potential correlates of HRQoL in a large representative sample of older adults, and (2) to investigate whether the relationships between HRQoL and potential factors differ as a function of HRQoL component (physical vs. mental) and/or age cohort (young-old vs. old–old).

Methods

This cross-sectional study included 802 older adults aged 60–79 years old. HRQoL was assessed using the SF-36 questionnaire. Functional fitness was assessed using the Senior Fitness Test. Physical activity was measured via the Baecke questionnaire. Demographic information, mental and health features were obtained through questionnaires.

Results

A multiple regression analysis showed that BMI (β = ?0.15, p?=?0.001), body strength (β =?0.21, p?<?0.001), aerobic endurance (β =?0.29, p?<?0.001), physical activity (β =?0.11, p?=?0.007), depressive symptoms (β = ?0.19, p?<?0.001), falls (β = ?0.19, p?<?0.001), and living alone (β = ?0.16, p?<?0.001) were all significantly related to HRQoL-SF-36 total score. The positive relation with aerobic endurance was significantly higher for the physical component of HRQoL, while the negative relation with living alone was significantly higher for the mental component. The positive relation of HRQoL with physical activity was significantly higher in old–old compared to young-old adults.

Conclusion

This data suggest that body composition, functional fitness, psycho-social factors, and falls are important correlates of HRQoL in old age. There are HRQoL-component and age-cohort differences regarding these correlates, underlying the need for specific strategies at the community level to promote HRQoL in older adults.

     

Acute effects of caffeine-containing energy drinks on physical performance: a systematic review and meta-analysis

Purpose

Caffeine-containing energy drinks (EDs) are currently used as ergogenic aids to improve physical performance in a wide variety of sport disciplines. However, the outcomes of previous investigations on this topic are inconclusive due to methodological differences, especially, in the dosage of the active ingredients and the test used to assess performance.

Methods

We performed a systematic review and meta-analysis of published studies to evaluate the effects of acute ED intake on physical performance. The search for references was conducted in the databases PubMed, ISI Web of Knowledge and SPORTDiscus until December 2015.

Results

Thirty-four studies published between 1998 and 2015 were included in the analysis. Using a random-effects model, effect sizes (ES) were calculated as the standardized mean difference. Overall, ED ingestion improved physical performance in muscle strength and endurance (ES = 0.49; p < 0.001), endurance exercise tests (ES = 0.53; p < 0.001), jumping (ES = 0.29; p = 0.01) and sport-specific actions (ES = 0.51; p < 0.001), but not in sprinting (ES = 0.14; p = 0.06). The meta-regression demonstrated a significant association between taurine dosage (mg) and performance (slope = 0.0001; p = 0.04), but not between caffeine dosage (mg) and performance (slope = 0.0009; p = 0.21).

Conclusion

ED ingestion improved performance in muscle strength and endurance, endurance exercise tests, jumping and sport-specific actions. However, the improvement in performance was associated with taurine dosage.

     

The validity of the Satisfaction with Life Scale in adolescents and a comparison with single-item life satisfaction measures: a preliminary study

Purpose

The validity of the life satisfaction measures commonly used among adults has been rarely examined in adolescent samples. The present research had two main goals: (1) to evaluate the structural validity of the Satisfaction with Life Scale (SWLS) among adolescents and to test measurement invariance across gender; (2) to compare the criterion and convergent validity of the SWLS and single-item life satisfaction measures among adolescents.

Methods

Three samples of Serbian adolescents were recruited for the present research. Study 1 (N = 481, M _age = 17.01 years) examined the structure of the SWLS via confirmatory factor analysis (CFA) and evaluated measurement invariance of the SWLS across gender by a multi-group CFA. Study 2 (N = 283, M _age = 17.34 years) and Study 3 (N = 220, M _age = 16.73 years) compared the convergent validity of the SWLS and single-item life satisfaction measures.

Results

The results of Study 1 supported the original one-factor model of the SWLS among adolescents and provided evidence for strong measurement invariance of the SWLS across gender. The findings of Study 2 and Study 3 showed that the SWLS and single-item measures were equally valid and strongly associated (r = .734 in Study 2 and r = .668 in Study 3). No substantial differences in correlations with school success and well-being indicators were found between the SWLS and single-item measures.

Conclusions

Our findings support the use of the SWLS among adolescents and indicate that single-item life satisfaction measures perform as well as the SWLS in adolescent samples.