Non-response bias in estimates of prevalence of club-based sport participation from an Australian national physical activity, recreation and sport survey.

BACKGROUND: An estimate of the prevalence of an activity derived from a sample survey is potentially subject to non-response bias, whereby people not involved in the activity are less likely to respond than those involved. Quantifying the extent of non-response bias is generally difficult, since it involves estimating differences between respondents for whom data is directly available from the survey, and non-respondents, for whom data is generally not directly or readily available. However, in the case of the Australian Exercise Recreation and Sport Survey (ERASS), comparative "gold standard" benchmarks exist for some aspects of the survey, in the form of state sporting association (SSA) registration databases, each of which purports to constitute a complete enumeration of club-based players of a particular sport. METHODS: ERASS estimates of the prevalence of participation in four major club-based team sports in the Australian state of Victoria in the year 2010 were compared with prevalences based on numbers of registered participants in the corresponding SSA databases. Comparisons were made for the adult population as a whole (ERASS scope being 15+ years of age), and for strata defined by age and geographical region. Because three of the four sports investigated are strongly sex-specific, no sex breakdowns were conducted. In each case the proportion of ERASS respondents reporting participation, with associated confidence limits, was compared with the corresponding SSA count expressed as a proportion of the population, to form an ERASS/SSA prevalence ratio with associated confidence limits. RESULTS: The 24 ERASS/SSA ratios ranged from 1.72 to 7.80. Most ratios lay in the range 2 to 3. The lower 95% confidence bound for the ratio was greater than 1.0 in 23 out of 24 cases. CONCLUSIONS: ERASS estimates of prevalence of these particular aspects of sport participation were higher than SSA estimates, to statistically significant degrees. The effect sizes (i.e. the discrepancies represented by the ratios) were large enough to be of great practical importance. It is conjectured that non-response bias is the most likely explanation for the discrepancies.

Population levels of sport participation: implications for sport policy.

BACKGROUND: Participation in sport can contribute to health-enhancing levels of leisure-time physical activity. There are recent reports that participation in sport in Australia is decreasing. However, these studies are limited to ages 15 years and over. METHODS: This study integrates sports club membership data from five popular team sports and investigates sport participation across the lifespan (4-100 years) by sex and region (metropolitan/non-metropolitan). RESULTS: Overall participant numbers per annum increased from 414,167 in 2010 to 465,403 in 2012 corresponding to a rise in the proportion of Victorian's participating in these sports from 7.5 % in 2010 to 8.3 % in 2012. The highest proportion of participants was in the 10-14 year age range, with participation rates of 36 % in 2010 and 40 % in 2012. There was a considerably lower participation rate in the 15-19 year age group compared to the 10-14 age group, in all three years studied, and the decline continued progressively with increasing age. Male and female age profiles of participation were generally similar in shape, but the female peak at age 10-14 was sharper than for the males, and conversely there were very few 4 year old female participants. Participation rates were generally higher in non-metropolitan than metropolitan areas; the difference increased with increasing age from 4 to 34 years, then steadily declined, reaching parity at around 60 years of age. CONCLUSIONS: It is a positive sign that participation in these popular sports increased by over 50,000 participants from 2010 to 2012. Large proportions of the population aged 5-14 participate in club based sport. Participation rates decline sharply in late adolescence, particularly for females, and while this may not be a concern from a broad health perspective so long as they transition into other forms of physical activity, it is certainly a matter of concern for the sport sector. It is recommended that sport policy places a higher priority on grass-roots participation and that sporting organisations are supported to prioritise the retention issues occurring during adolescence, particularly for females so as to maximise the potential for sport to maintain its positive contribution to population wellbeing.

Trends in body image of adolescent females in metropolitan and non-metropolitan regions: a longitudinal study.

BACKGROUND: Body dissatisfaction is associated with a range of adverse outcomes, including impaired psychological health, low physical activity and disordered eating. This longitudinal study used the Factors Influencing Transitions in Girls' Active Leisure and Sport (FITGALS) dataset to examine trends in body image of adolescent females. Specifically, the study examined satisfaction with body size, physical appearance and dieting behaviour for two cohorts at transitional life phases in two geographic regions longitudinally over a 3-year period. METHODS: A sample of 732 adolescent females in Grade 7 (n = 489, 66.8 %) and Grade 11 (n = 243, 33.2 %) at randomly selected Australian metropolitan and non-metropolitan secondary schools responded to a questionnaire in three successive years from 2008 to 2010. Participants reported perceptions about their body size and physical appearance and whether they were, or ought to be, on a diet. The data were analysed using a series of longitudinal logistic regression models. RESULTS: Dieting and dissatisfaction with body size significantly increased over time and more so for older than younger girls. Region significantly moderated the effect of grade level regarding dissatisfaction with body size but not dieting. In non-metropolitan regions, those in the younger cohort were significantly more likely to be dissatisfied with their body size than the older cohort; whereas in metropolitan regions, those in the older cohort were significantly more likely to be dissatisfied with their body size than the younger cohort. Adolescent female's perceptions of their appearance were unchanged over time, region and grade level. CONCLUSIONS: Differences across time, region and grade level were found among adolescent females on body size and dieting behaviour, but not physical appearance. Adolescent females experience early and increasing body size dissatisfaction and dieting as they age, but stable perceptions of physical appearance. Age and geographic region are important considerations for the timing and targeting of interventions to address body image concerns. Further investigation of regional differences in body image perceptions and factors that affect these is warranted. The findings of this study highlight the ongoing need for strategies during adolescence to promote a healthy appreciation of body size and appearance.

The contribution of sport participation to overall health enhancing physical activity levels in Australia: a population-based study.

BACKGROUND: The contribution of sport to overall health-enhancing leisure-time physical activity (HELPA) in adults is not well understood. The aim was to examine this in a national sample of Australians aged 15+ years, and to extend this examination to other ostensibly sport-associated activities. METHODS: The 2010 Exercise, Recreation and Sport Survey (ERASS) was conducted by telephone interview in four quarterly waves. Data from this survey were analysed to categorise leisure-time physical activity (LTPA) as HELPA or non-HELPA, and to categorise HELPA activities and sessions of HELPA activity by setting and frequency. The contribution of sport to HELPA was estimated, both directly through activities and settings classified as sport per se, and indirectly through other fitness activities ostensibly related to preparation for sport and enhancement of sport performance. RESULTS: Of 21,602 respondents, 82 % reported some LTPA in the 12 months prior to the survey. In aggregate, respondents reported 37,020 activity types in the previous 12 months, of which 94 % were HELPA. Of HELPA activities, 71 % were non-organised, 11 % were organised but not sport club-based, and 18 % were sport club-based. Of all sport activities, 52 % were HELPA. Of sport HELPA, 33 % was sport club-based and 78 % was undertaken ≥12 times/year. Sport club members were significantly more likely to have participated in running, but significantly less likely to have participated in walking or aerobics/fitness training, than non-club members. CONCLUSIONS: Club sport participation contributes considerably to LTPA at health enhancing levels. Health promotion policies, and more specifically physical activity policies, should emphasize the role of sport in enhancing health. Sport policy should recognise the health-promoting role of community-based sport in addition to the current predominant focus on elite pathways.

Transition in participation in sport and unstructured physical activity for rural living adolescent girls.

Physical activity (PA) is important for lifelong health; however, participation is lower in rural compared with metropolitan areas and declines during adolescence, particularly for girls. It is likely that this decline is related to the number of life transitions that occur during adolescence. This qualitative study examined the views of active rural living girls regarding the factors affecting their sport and PA participation, using the socioecological model. Twenty-seven girls aged 16-17 from four schools participated in semi-structured focus group discussions. Content and thematic analysis was conducted from verbatim transcripts using NVivo. The girls enjoyed involvement in community club sport with friends and they reported living in communities where participation in sport was a major form of social interaction. However, the desire to succeed educationally was a critical factor affecting their participation in sport and PA and influenced their movement from structured club sport to more flexible, but socially isolated individual activities. It is recommended that future longitudinal research should track rural living adolescent females as they complete secondary school, in order to better understand the influence of educational priorities upon sport and PA participation and to identify practical strategies for both schools and community organizations to foster continuing participation throughout this crucial period of life transition.

The influence of a Healthy Welcoming Environment on participation in club sport by adolescent girls: a longitudinal study.

BACKGROUND: This study investigated the perceived influence of a Healthy Welcoming Environment (HWE) on participation in sports clubs among adolescent girls, and how these perceptions changed longitudinally. HWE was defined in terms of a set of health promotion policies advocated by a health promotion foundation as the basis of sport club health promotion practice to promote structural reform in state sporting organisations and their affiliated associations and clubs. These included sports injury prevention, smoke-free, responsible serving of alcohol, sun protection, healthy eating, and welcoming and inclusive environments. METHODS: Year 7 and 11 female students from metropolitan (n = 17) and non-metropolitan secondary schools (n = 14) in Australia were invited to participate in three annual surveys. These surveys collected information about current or past membership of a sports club and the influence of HWEs on their decision to participate (or not) in a sports club. RESULTS: Year 7 (n = 328; 74.5%) and Year 11 (n = 112; 25.5%) female students completed all three waves (19.6% response rate; 82.7 and 74.0% retention rate). Most agreed that characteristics of HWEs were a positive influence on their participation in sports clubs, except those relating to alcohol and Sunsmart. Welcoming factors had consistent high agreement among respondents. Alcohol and friendliness factors of the club were regarded as being positively influential by higher percentages of non-metropolitan than metropolitan respondents. CONCLUSIONS: Welcoming factors were the most positive influences on decisions to participate in sports clubs. These factors may be important in reducing barriers to sport participation. Strategies supporting the social environment within sports clubs should be prioritised.

Contaminant loads and hematological correlates in the harbor seal (Phoca vitulina) of San Francisco Bay, California.

An expanding body of research indicates that exposure to contaminants may impact marine mammal health, thus possibly contributing to population declines. The harbor seal population of the San Francisco Bay (SFB), California, has suffered habitat loss and degradation, including decades of environmental contamination. To explore the possibility of contaminant-induced health alterations in this population, blood levels of polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenyl ethers (PBDEs) were quantified in free-ranging seals; relationships between contaminant exposure and several key hematological parameters were examined; and PCB levels in the present study were compared with levels determined in SFB seals a decade earlier. PCB residues in harbor seal blood decreased during the past decade, but remained at levels great enough that adverse reproductive and immunological effects might be expected. Main results included a positive association between leukocyte counts and PBDEs, PCBs, and DDE in seals, and an inverse relationship between red blood cell count and PBDEs. Although not necessarily pathologic, these responses may serve as sentinel indications of contaminant-induced alterations in harbor seals of SFB, which, in individuals with relatively high contaminant burdens, might include increased rates of infection and anemia.

Development of body oxygen stores in harbor seals: effects of age, mass, and body composition.

Harbor seal pups are highly precocial and can swim and dive at birth. Such behavioral maturity suggests that they may be born with mature body oxygen stores or that stores develop quickly during the nursing period. To test this hypothesis, we compared the blood and muscle oxygen stores of harbor seal pups, yearlings, and adults. We found that pups had smaller oxygen stores than adults (neonates 57%, weaned pups 75%, and yearlings 90% those of adults), largely because neonatal myoglobin concentrations were low (1.6+/-0.2 g% vs. 3.8+/-0.3 g% for adults) and changed little during the nursing period. In contrast, blood oxygen stores were relatively mature, with nursing pups having hematocrit (55%+/-0.2%), hemoglobin (21.7+/-0.4 g%), and blood volume (12.3+/-0.5 mL/kg) only slightly lower than the corresponding values for adults (57%+/-0.2%, 23.8+/-0.3 g %, and 15.0+/-0.5 mL/kg). Because neonatal pups had relatively high metabolic rates (11.0 mL O2/kg min), their calculated aerobic dive limit was less than 50% that of adults. These results suggest that harbor seals' early aquatic activity is primarily supported by rapid development of blood, with immature muscle oxygen stores and elevated use rates limiting aerobic diving ability.

Lid splitting and posterior lamella cryosurgery for congenital and acquired distichiasis.

Congenital distichiasis is a rare condition with an accessory row of lashes at the Meibomian gland orifices. We suggest "acquired distichiasis" as an appropriate term for the accessory row of lashes in or near the Meibomian gland orifices, occurring as a result of such conditions as Stevens-Johnson syndrome, ocular pemphigoid, or chemical and physical injuries. We report a new treatment technique in which the eyelid is divided along the gray line then followed by cryotherapy to the posterior lid lamella. This removes the distichiatic lashes without damaging the normal lashes in the anterior lid lamella and avoids depigmentation. Histologic examination demonstrates the aberrant lashes result from a metaplasia of tissues in or around the Meibomian glands. Thirteen eyelids with acquired distichiasis and four eyelids with congenital distichiasis have been followed up for eight to 48 months. All have been greatly improved.

Plasma catecholamine concentration during sedation in ventilated patients requiring intensive therapy.

The effects of isoflurane and midazolam sedation on the catecholamine responses of ventilated patients were studied over a 24-h period. Sixty ventilated patients admitted to our intensive therapy unit were allocated randomly to receive either isoflurane or midazolam sedation. Arterial blood samples for plasma catecholamine concentrations were taken at baseline, 6 h after starting sedation and at the end of the study period. Patients sedated with isoflurane showed a progressive reduction in both adrenaline and noradrenaline concentrations during the period of sedation which reached statistical significance for adrenaline at 6 h (p less than 0.02) and at the end of the study (p less than 0.001). Patients sedated with midazolam showed no significant changes of adrenaline or noradrenaline concentrations. Overall, a more satisfactory degree of sedation was achieved with isoflurane.

Petriellidium (Allescheria) boydii orbital and brain abscess treated with intravenous miconazole.

A previously healthy 4-year-old boy suffered a penetrating injury to his left orbit and left frontal lobe, which resulted in an infection by Petriellidium boydii. The patient was successfully treated with intravenous miconazole and multiple debridements.

Voluntary entropion.

Voluntary entropion, which has been reported only once before, was photographically documented in a 12-year-old girl. The lower-eyelid retractors and protractors were clinically normal. The postulated mechanism of the entropion was selective innervational control of separate components of the orbicularis oculi complex, which allowed the preseptal portion to override the pretarsal portion.

Sheep botfly: ophthalmomyiasis externa.

Sheep botfly (Oestrus ovis) conjunctival infestation is rare in North America but is common in other parts of the world. The author treated 30 patients with this type of conjunctivitis in Jerusalem in 1981 and 1982. The conjunctivitis may vary from mild to severe (pseudo-orbital cellulitis). Features of the conjunctivitis include pale edema, linear superficial punctate keratopathy and the presence of larvae in the conjunctival sac. Conjunctival scrapings revealed a preponderance of polymorphonucleocytes.

Ranking clinical problems and ocular diseases in ophthalmology: an innovative approach to curriculum design.

The MD program of the Faculty of Health Sciences, McMaster University, Hamilton, Ont., has used a problem-based, self-directed, small-group learning approach to medical education since 1969. Substantial curriculum revision was begun in 1983 as part of a process of institutional renewal. A faculty survey of all academic clinicians in the Division of Ophthalmology, Department of Surgery, was carried out in 1984 to determine which problems and diseases the teaching faculty thought had the highest priority for student learning. The results have been used by educational planners in revising the curriculum. They have also served to clarify faculty members' expectations of students within an ophthalmology rotation.

Sensitivity and specificity of the diagnosis of periocular lesions by oculoplastic surgeons.

BACKGROUND: A few studies have assessed the sensitivity of ophthalmologists in diagnosing periocular lesions. However, no study has assessed their diagnostic specificity or the degree to which they overdiagnose various lesions. We performed a study to determine the sensitivity and specificity of oculoplastic surgeons' preoperative diagnoses of common and uncommon periocular lesions. METHODS: Using the patient records of four oculoplastic ophthalmologists, we reviewed all charts documenting periocular surgery in which lesions were excised and sent for biopsy. For each of 358 cases we recorded the preoperative diagnosis as listed by the surgeon and the postoperative diagnosis as reported by the pathologist. Each preoperative diagnosis was then scored as correct or incorrect. The relative number of each type of lesion was determined, and the ophthalmologists' sensitivity and specificity were calculated. RESULTS: The sensitivity and specificity for the eight most frequently lesions were (in order of frequency) basal cell carcinoma 92.1% and 81.6% respectively, papilloma 81.6% and 66.0%, cyst 66.7% and 69.7%, nevus 53.6% and 75.0%, seborrheic keratosis 27.8% and 71.4%, chalazion 93.3% and 100.0%, squamous cell carcinoma 33.3% and 55.6%, and xanthelasma 100.0% and 76.9%. The values for melanoma were 50.0% and 28.6%, for sebaceous gland carcinoma 0.0% and 100.0%, and for uncommon lesions (nonspecific inflammation, actinic keratosis, granuloma, cavernous hemangioma, folliculitis, benign sweat gland tumour, eccrine hidrocystoma and collagenous tissue) 27.8% and 57.1%. The overall accuracy in lesion identification was 70.0%. INTERPRETATION: Although ophthalmologists have excellent diagnostic sensitivity and specificity for some types of lesion, such as basal cell carcinoma and chalazion, the identification of other lesion types, such as cyst, squamous cell carcinoma and possibly melanoma and sebaceous gland carcinoma, is less optimal.

Blastogenesis and interleukin-2 receptor expression assays in the harbor seal (Phoca vitulina).

Two in vitro functional assays were developed to evaluate mitogen-induced responses of peripheral blood mononuclear leukocytes (PBML) from free-ranging harbor seals, Phoca vitulina. Lymphocyte proliferation was measured by a standard blastogenesis assay following optimization of culture conditions including mitogen concentration, cell density, and incubation time. These optimized parameters, with the exception of incubation time, were subsequently employed to measure lymphocyte activation by analytical flow cytometry using fluorochrome-based identification of cell surface interleukin-2 receptor (IL-2r) expression. Baseline values established for free-ranging harbor seals had extensive animal variability; there was evidence that the samples were derived from a group of animals with a normal distribution. Positive correlations were observed between blastogenesis assays, and between blastogenesis and activation assays, when using pokeweed or concanavalin A as the stimulus. However, no relationship was found in the expression of the IL-2r induced by these mitogens. This result supports the contention that the two mitogens stimulate different lymphocyte subpopulations. This was observed only with the IL-2r expression assay because of its unique ability to measure the number of T lymphocytes initially activated rather than the ultimate number of progeny cells identified by blastogenesis. Both assays, used concurrently, should provide a more comprehensive representation of lymphocyte competence and serve as a measure of animal health.

An analysis of the forces required to drag sheep over various surfaces.

Some occupational health and safety hazards associated with sheep shearing are related to shearing shed design. One aspect is the floor of the catching pen, from which sheep are caught and dragged to the shearing workstation. Floors can be constructed from various materials, and may be level or gently sloping. An experiment was conducted using eight experienced shearers as participants to measure the force exerted by a shearer when dragging a sheep. Results showed that significant changes in mean dragging force occurred with changes in both surface texture and slope. The mean dragging forces for different floor textures and slopes ranged from 359 N (36.6 kg) to 423N (43.2 kg), and were close to the maximum acceptable limits for pulling forces for the most capable of males. The best floor tested was a floor sloped at 1:10 constructed of timber battens oriented parallel to the path of the drag, which resulted in a mean dragging force 63.6N (15%) lower than the worst combination.

A comparison of rat SPECT images obtained using (99m)Tc derived from 99Mo produced by an electron accelerator with that from a reactor.

Recent shortages of molybdenum-99 ((99)Mo) have led to an examination of alternate production methods that could contribute to a more robust supply. An electron accelerator and the photoneutron reaction were used to produce (99)Mo from which technetium-99m ((99m)Tc) is extracted. SPECT images of rat anatomy obtained using the accelerator-produced (99m)Tc with those obtained using (99m)Tc from a commercial generator were compared. Disks of (100)Mo were irradiated with x-rays produced by a 35 MeV electron beam to generate about 1110 MBq (30 mCi) of (99)Mo per disk. After target dissolution, a NorthStar ARSII unit was used to separate the (99m)Tc, which was subsequently used to tag pharmaceuticals suitable for cardiac and bone imaging. SPECT images were acquired for three rats and compared to images for the same three rats obtained using (99m)Tc from a standard reactor (99)Mo generator. The efficiency of (99)Mo-(99m)Tc separation was typically greater than 90%. This study demonstrated the delivery of (99m)Tc from the end of beam to the end user of approximately 30 h. Images obtained using the heart and bone scanning agents using reactor and linac-produced (99m)Tc were comparable. High-power electron accelerators are an attractive option for producing (99)Mo on a national scale.