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PubMed2005

National variations in morbid obesity and bariatric surgery use.

BACKGROUND: Exploring bariatric surgery use provides data on effective treatment allocation. This study analyzed national rates of bariatric surgery use and the burden of morbid obesity by gender, census region, and age. STUDY DESIGN: Patients 18 years of age or older undergoing bariatric surgery were identified from the US 2002 Nationwide Inpatient Sample, and the national morbidly obese population 18 years of age or older was determined using the Centers for Disease Control and Prevention 2002 Behavioral Risk Factor Surveillance System databases. General population data were obtained from 2000 census data. Annual rates of bariatric surgery procedures were determined by gender, age group, and census region (Northeast, Midwest, South, and West). Rate ratios were calculated and significance tested through 95% confidence intervals (95% CI), accounting for the Nationwide Inpatient Sample and Behavioral Risk Factor Surveillance System sampling design. RESULTS: In 2002, a national cohort of 69,490 bariatric surgery patients was identified. Of these patients 85% were women and 76% were ages 18 to 49 years. The prevalence of morbid obesity (body mass index > or = 40 kg/m(2)) in the US in 2002 was 1.8%; 60% of morbidly obese people were women, and 63% were ages 18 to 49 years. The rates of bariatric surgery procedures per 100,000 morbidly obese individuals ranged from a low of 139 in men aged 60 years and older in the Midwest to a high of 5,156 in women ages 40 to 49 years in the Northeast. For both men and women, bariatric surgery rates in the West and Northeast were 1.35 (95% CI 1.31 to 1.40, p < 0.05) to 4.51 (95% CI 4.15 to 4.89, p < 0.05) times higher than in the South, respectively; rates in the Midwest were similar to those in the South. CONCLUSIONS: National estimates suggest that bariatric surgery rates do not parallel the burden of morbid obesity by region or age. Additional evaluation of these differences is necessary for optimal bariatric surgery use.

Adolescent↗
PubMed1997

A critique of the methodology of research studies evaluating massage.

This review examines 14 research studies which have been undertaken to evaluate massage. The review offers a critique of the methodology of these studies, and issues relating to the research design, samples, measurement tools, analysis and the massage intervention are discussed. The critique highlights several key issues relating to the design of the studies and concludes with some recommendations for future research studies evaluating massage.

Bias↗
PubMed2003

Comparison of tracheal aspirates and bronchoalveolar lavage in racehorses. 1. Evaluation of cytological stains and the percentage of mast cells and eosinophils.

OBJECTIVE: To compare a fast Romanowsky cytological stain (Diff-Quik) and Leishman's stain for the detection of mast cells in samples from the lower airways of racehorses, and to compare the proportion of mast cells and eosinophils in the total inflammatory cells in tracheal aspirate (TA) with those in paired bronchoalveolar lavage (BAL) samples. DESIGN: Retrospective case series of 48 young Thoroughbred and Standardbred racehorses. PROCEDURE: Fifty-one paired TA and BAL samples were collected after treadmill exercise from 48 horses with poor racing performance. Two slides were prepared from each sample; one was stained with Diff-Quik stain and the other with Leishman's stain. Differential cell counts of eosinophils and mast cells were recorded from each slide. Comparison of the suitability of the stains for the detection of mast cells, and comparisons of eosinophil and mast cell percentages in TA and BAL samples were analysed using the non-parametric Wilcoxon matched pairs test. RESULTS: Percentages of mast cells were significantly higher in Leishman than in Diff-Quik stained slides in both TA (P = 0.03) and BAL samples (P < 0.0001). Mast cell percentages were significantly higher in BAL than in TA samples using Leishman's stain (P < 0.0001). There was no significant difference in eosinophil percentages between TA and BAL samples (P = 0.07). CONCLUSIONS: Fast Romanowsky type stains (for example Diff-Quik) are not appropriate for the detection of mast cells in samples from the equine lower respiratory tract. Therefore, a metachromatic stain that reliably identifies mast cells (for example Leishman's) should be used if evaluation of mast cells in lower respiratory tract is undertaken. Mast cells are predominantly found in the distal small airways and alveoli sampled with a BAL. In contrast, eosinophils appear to be evenly distributed in the lower respiratory tract. However, high percentages of eosinophils are occasionally found only in TA samples. We recommend that both a TA and BAL be used for the evaluation of eosinophils and mast cells within the equine lower respiratory tract.

Animals↗
PubMed2005

Evaluation of enzyme-linked immunosorbent assays performed on milk and serum samples for detection of paratuberculosis in lactating dairy cows.

OBJECTIVE: To determine whether results obtained for milk and serum samples with ELISAs intended for diagnosis of paratuberculosis in dairy cows were comparable to results obtained by means of mycobacterial culture of fecal samples. DESIGN: Cross-sectional study. ANIMALS: 689 lactating dairy cows in 9 Ontario herds. PROCEDURE: Milk, serum, and fecal samples were obtained from all cows. Fecal samples were submitted for mycobacterial culture. Serum samples were tested with a commercially available ELISA for antibodies against Mycobacterium paratuberculosis, and preserved milk samples were tested with an indirect ELISA for antibodies against M paratuberculosis. RESULTS: Results were positive for 130 of the 689 (18.9%) serum samples, 77 of the 689 (11.1%) milk samples, and 72 of the 689 (10.4%) fecal samples. The level of agreement between results for milk and serum samples was only moderate. Proportions of positive results for serum and fecal samples were significantly different, but proportions of positive results for milk and fecal samples were not significantly different. In addition, results for milk samples had a higher level of agreement with results of mycobacterial culture than did results for serum samples. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the indirect ELISA used on milk samples may be a convenient method of detecting paratuberculosis in dairy herds.

Animals↗
PubMed1994

Use of response surface statistical designs to detect effects of biologic response modifiers such as IL-2.

Recently many biologic response modifiers have been discovered or produced, but their effects are incompletely understood. The effects of these agents are complicated by their dependence not merely upon the administered dose, nor even the interval of time between administration and observation of effect, but also because of the cascade of interactions that can be invoked. Conventional experimental designs that test a specific combination looking for statistical significance, and that involve doing a series of studies varying one parameter at a time, are likely to require large numbers of animals or patients to answer the question of possible effect, and have a high likelihood of missing the effect altogether because of not selecting the correct combination of parameter levels. Response surface designs are intended for simultaneous multiparameter evaluation and so are less likely to miss an effect. However, if fixed sample designs are employed, the number of subjects required may still be quite large. Sequential designs based on response surface models have been used in other fields but are only now being applied in the fields of biology and medicine. We have explored the use of these designs to evaluate the potential usefulness of interleukin-2 (IL-2) to increase tumor uptake of subsequently administered antibody in nude mice. We found that these methods enabled us to efficiently determine optimal combinations of dose of IL-2 and interval of time between IL-2 and antibody administration for enhancement. Enhancement of tumor uptake of the antibody by IL-2 was substantial in amount and sufficient to stimulate studies in patients where we will use similar sequential methodology for trial design.

Animals↗
PubMedDate not supplied

[Nursing research in Italy, 1998-2001].

Academic education and professional role, both enhancing status and opening new paths for further developments. Consequently, there is a wide a compulsory interest to develop scientific research in the nursing field and to increase the number of studies published in the nation each year. This study reviewed the areas of inquiry and characteristics of research articles published in Italian journals from 1998 throughout 2001. Phenomena of interest, research design, sampling, and internal consistency have been used as evaluation criteria. Of 64 articles identified, only 52 have been reviewed (81%) because matching the selection criteria. Of the reviewed studies, 73% focus on clinical aspects, 21.2% on management, and 5.8% on nursing education. The majority of the reviewed studies use cross or longitudinal observational design, correlational (3.8%), or quasiexperimental design (5.2%). Convenience selection was the most used sampling method when reported. Data analysis was mostly done using descriptive statistics with only few exceptions. The majority of the reviewed studied adopt a quantitative approach. A nurse was principal investigator only in 58% of the studies.

Adult↗
PubMed1999

The importance of shared environmental influences in explaining the overlap between mother's parenting and sibling relationships: reply to Neale (1999)

This article addresses concerns raised by M. C. Neale (1999) in his commentary on the D. A. Bussell et al. (1999) Nonshared Environment in Adolescent Development (NEAD) study. These concerns fall into two categories: (a) model assumptions and sample design and (b) testing of alternative models. The validity of the assumptions of quantitative genetic models is a concern for all researchers in this area. Discussion of those assumptions in this reply is brief and focuses on those most relevant to the NEAD sample. The two alternative models proposed by Neale were designed to provide alternatives to the large shared environmental effect found in the original report of Bussell et al. Because these alternative models did not provide a better fit, the appropriateness of Bussell et al.'s basic model and the importance of shared environmental influences for explaining the association among family subsystems are supported.

Adolescent↗
PubMed2007

Adolescent passengers of drunk drivers: a multi-level exploration into the inequities of risk and safety.

AIMS: This study determined the individual-, neighbourhood- and provincial-level effects of rural residence, socio-economic status (SES), substance use and driving behaviours on adolescents' riding with a drunk driver (RDD). DESIGN: Multi-level study based on cross-sectional self-reported anonymous data from the Student Drug Use Survey in the Atlantic Provinces (SDUSAP) and Census Canada data, merged on the postal code of participating schools. The sample design of the SDUSAP was a single-stage cluster sample of randomly selected classes stratified by grade and region. SETTING: The Atlantic provinces of Canada. PARTICIPANTS: A total of 12 990 students in junior and senior high schools, with an average age of 15 years, participated in the 2002 SDUSAP. MEASUREMENTS: The outcome variable was past-year RDD. The main individual-level independent variables were SES, rural residence, substance use and driving behaviours. The school-neighbourhood independent variables were the prevalence of heavy episodic drinking, driving under the influence of alcohol, driver's licence, highest level of educational attainment and low income. FINDINGS: The prevalence of RDD was 23.3% in 2002. Among students in grades 9-12, lower family SES, rural residence, substance use and driving under the influence were found to be independent individual-level risk factors for RDD; having a driver's licence was found to be protective. At the provincial and school-neighbourhood levels, a high prevalence of driving under the influence of alcohol and low educational attainment were found to be independent risk factors for RDD after taking into account individual characteristics. CONCLUSIONS: This study provides evidence that inequities exist in the options for adolescents to be ensured of passenger safety, and that interventions aimed at decreasing the extent to which adolescents engage in riding with a drunk driver should be based on conceptual approaches that recognize ecological factors as well as individual-level susceptibility.

Accidents, Traffic↗
PubMedDate not supplied

Statistical methods for estimating attributable risk from retrospective data.

This paper extends Levin's measure of attributable risk to adjust for confounding by aetiologic factors other than the exposure of interest. One can estimate this extended measure from case-control data provided either (i) from the control data one can estimate exposure prevalence within each stratum of the confounding factor; or (ii) one has additional information available concerning the confounder distribution and the stratum-specific disease rates. In both cases we give maximum likelihood estimates and their estimated asymptotic variances, and show them to be independent of the sampling design (matched vs. random). Computer simulations investigate the behaviour of these estimates and of three types of confidence intervals when sample size is small relative to the number of confounder strata. The simulations indicate that attributable risk estimates tend to be too low. The bias is not serious except when exposure prevalence is high among controls. In this case the estimates and their standard error estimates are also highly unstable. In general, the asymptotic standard error estimates performed quite well, even in small samples, and even when the true asymptotic standard error was too small. By contrast, the bootstrap estimate tended to be too large. None of the three confidence intervals proved superior in accuracy to the other two. Thus there appears no advantage in using the log-based interval suggested by Walter which is always longer than the simpler symmetric interval.

Adult↗
PubMed2005

Assessment of the rangelands of southwestern Santiago del Estero, Argentina, for grazing management and research.

Native rangelands of the southwest part of the province of Santiago del Estero, Argentina, are a key source of forage for cow-calf operations. The objectives of this study were to delineate the ecosystem units of the area, to describe the associated plant communities and to interpret the role that physical factors and disturbances such as fire and grazing have had in the changes of the structure of these plant communities. This information is needed for developing recommendations for grazing management, for prescribing appropriate improvement practices (e.g. shrub control, prescribed fire) and as guidelines for future research. The ecosystem was divided into smaller units using a hierarchical method, the categories of practical importance being 'range unit' and 'range site'. They represent the catchment and hillslope scale of the water runoff-runon phenomenon, respectively. Vegetation was sampled using a block and cluster sampling design, registering tree, shrub, forb and grass species frequency, and the standing aerial biomass of the herbaceous layer in a sampling unit=1 ha. Environmental data (topographic position, fire frequency, current and past use, and tree and shrub cover) were also registered for each sampling unit. Indirect ordination of sampling units classified according to range units and range sites, and correlation with environmental variables were performed using multidimensional scaling (MDS) as well as the vector fitting technique. Standing forage and stocking rate were estimated from biomass data. Results indicate that 'range site' is the ecosystem unit that should be considered for management purposes since it correlates well with plant communities: tall, hardwood forests are located on upland sites, woodlands are located on midland sites and savannas are located on lowland sites. Dense shrub thickets dominate in areas rated in poor condition, irrespective of range site. Disturbances such as fire and current and past use have a significant positive and negative correlation with range condition, respectively, suggesting that a state and transition model would explain vegetation dynamics better than the succession model. The estimated stocking rate in lowland sites in good condition was 2 ha UG(-1), while in upland sites in poor condition the stocking rate was 90 ha UG(-1). Active (fire, mechanical treatments) rather than passive (grazing management) methods should be used for range improvement in order to achieve the full potential of the ecosystem.

Agriculture↗
PubMed2026

Amplification-Free Nanopore Sequencing for Herpesvirus DNA Detection in Intraocular Fluids.

PURPOSE: To evaluate the feasibility of amplification-free nanopore sequencing for detecting herpesvirus DNA in intraocular fluid using multiplex polymerase chain reaction (mPCR)-characterized herpesvirus-positive and herpesvirus-negative samples. DESIGN: Retrospective, single-center, cross-sectional study. PARTICIPANTS: This study included 42 patients with uveitis whose intraocular fluid samples were examined by mPCR, including 20 mPCR-positive samples (all positive for herpesviruses) and 22 mPCR-negative samples. METHODS INTERVENTION OR TESTING: DNA extracted from intraocular fluid samples underwent ligation-based library preparation without whole-genome amplification and was sequenced on the MinION platform with Flongle flow cells for untargeted analysis. Nanopore sequencing results were compared with mPCR findings, and associations between nanopore-derived virus-specific read counts and corresponding herpesvirus DNA copy numbers measured by mPCR were assessed. MAIN OUTCOME MEASURES: Primary outcome measure was concordance between nanopore sequencing and mPCR in herpesvirus species identification. Secondary outcome measures included nanopore sequencing detection rates stratified according to mPCR-measured herpesvirus DNA copy numbers and correlations between nanopore sequencing-derived virus-specific read counts and mPCR-measured herpesvirus DNA copy numbers. RESULTS: Among 20 mPCR-positive intraocular fluid samples, nanopore sequencing identified viral DNA from the same herpesvirus species detected by mPCR in 15 (75.0%), indicating species-level concordance. None of the 22 mPCR-negative samples contained virus-specific reads. Among the 22 herpesvirus targets identified in the 20 mPCR-positive samples, herpesvirus DNA copy numbers measured by mPCR were significantly higher in nanopore-positive than in nanopore-negative targets (P = 0.015). Nanopore detection rates increased with increasing herpesvirus DNA copy numbers measured by mPCR: 3 of 6 targets (50.0%) with <105 copies/mL, 2 of 4 (50.0%) with 105-106 copies/mL, and 12 of 12 (100%) with >106 copies/mL (P = 0.021). Nanopore sequencing-derived virus-specific read counts correlated positively with herpesvirus DNA copy numbers measured by mPCR (r = 0.76, P = 0.0004). CONCLUSIONS: Amplification-free nanopore sequencing demonstrated the feasibility of detecting herpesvirus DNA in intraocular fluid samples, with detection performance dependent on herpesvirus DNA load. This simplified workflow may provide complementary information regarding viral DNA burden in minute ocular samples. FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Herpesvirus↗
PubMed2002

Use of inappropriate prescription drugs by older people.

OBJECTIVES: To determine the prevalence and predictors of inappropriate drug prescribing defined by expert national consensus panel drug utilization review criteria for community-dwelling older people. DESIGN: Survey. SETTING: Five adjacent urban and rural counties in the Piedmont area of North Carolina. PARTICIPANTS: A stratified random sample of participants from the fourth (n = 3,234) and seventh (n = 2,508) waves of the Duke Established Populations for Epidemiological Studies of the Elderly. MEASUREMENTS: The prescribing appropriateness for digoxin, calcium channel blockers, angiotensin-converting enzyme inhibitors, histamine(2) receptor antagonists, nonsteroidal antiinflammatory drugs (NSAIDs), benzodiazepines, antipsychotics, and antidepressants as determined by explicit criteria (through Health Care Financing Administration expert consensus panel drug utilization review criteria for dosage, duplication, drug-drug interactions and duration, and U.S. and Canadian expert consensus panel criteria for drug-disease interactions). Multivariable analyses, using weighted data adjusted for sampling design, were conducted to assess the association between inappropriate prescribing and demographic, health-status, and access-to-healthcare factors cross-sectionally and longitudinally. RESULTS: We found that 21.0 of the fourth wave and 19.2 of the seventh wave participants who used one or more agents from the eight drug classes had one or more elements identified as inappropriate. The therapeutic classes with the most problems were benzodiazepines and NSAIDs. The most common problems were with drug-disease interactions and duration of use. Longitudinal multivariable analyses found that participants who were white (adjusted odds ratio (AOR) = 1.67, 95 confidence interval (CI) = 1.28-2.17), were married (AOR = 1.40, 95% CI = 1.01-1.93), had arthritis (AOR = 1.74, 95% CI = 1.27-2.38), had one or more physical function disabilities (AOR = 1.42, 95% CI = 1.02-1.96), and had inappropriate drugs prescribed at wave 4 (AOR = 6.87, 95% CI = 5.11-9.22) were more likely to have inappropriate prescribing at wave 7. CONCLUSION: These results indicate that inappropriate prescribing is common among community-dwelling older people and persists over time. Longitudinal studies in older people are needed to examine the impact of inappropriate drug prescribing on health-related outcomes.

Aged↗
PubMed2001

Is nicotine dependence related to smokers' support for restrictions on smoking?

OBJECTIVES: To examine the relationship between nicotine dependence and attitudes, predicted behaviours and support regarding restrictions on smoking. DESIGN: Population-based, computer-assisted, telephone survey of adults in Ontario, Canada using a two-stage stratified sampling design; 1764 interviews were completed (65% response rate) yielding 424 (24%) cigarette smokers, of whom 354 (83%) smoked daily. The Heaviness of Smoking Index was used as a measure of nicotine dependence. MAIN OUTCOME MEASURE: Attitudes toward smoking restrictions, predicted compliance with more restrictions, and support for total smoking bans. RESULTS: Attitudes favorable to smoking restrictions tended to decrease with increased nicotine dependence, but the associations were not statistically significant after adjusting for demographic variables. Predicted compliance with more restrictions on smoking decreased with higher levels of dependence, as did support for a total ban on smoking in restaurants, workplaces, bingo halls, and hockey arenas. Support for smoking bans in food courts, family fast food restaurants, and bars and taverns did not vary significantly with level of nicotine dependence. CONCLUSIONS: Level of nicotine dependence is associated with intended behaviors and support for smoking restrictions in some settings. These results have implications for tobacco control programs and policies.

Adolescent↗
PubMed1988

Effect of food on the bioavailability of a slow-release theophylline formulation.

A study was conducted in two groups of healthy volunteers to assess whether the time of administration (10 min before the meal versus 60 min after the meal) influences the pharmacokinetics and absorption kinetics of a slow-release theophylline product (Teonova). In the first group (Group A, n = 10), the drug was given in a paired-sample design as a single dose of 600 mg before and after breakfast with an interval of at least 1 week between the two administrations. In the second group (Group B, n = 10), Teonova was given by the same study design before and after dinner. In all cases, time curves of theophylline plasma levels were determined by collecting serial blood samples 24 h after dosing and analysed pharmacokinetically through model-independent methods. In Group A, curves obtained before and after the meal were fully superimposable, and no difference was found between the pharmacokinetic parameters determined in either condition. The same result was obtained in Group B. Our results indicate that, after single dose, the two different times of administration that we tested were equivalent in pharmacokinetic terms.

Adult↗
PubMed2006

Prevalence of diabetes and impaired fasting glucose in Korea: Korean National Health and Nutrition Survey 2001.

OBJECTIVE: The purpose of this study was to estimate the prevalence of diabetes and impaired fasting glucose (IFG) and their association with risk factors in the Korean population. RESEARCH DESIGN AND METHODS: The Korean National Health and Nutrition Survey 2001 was a nationally representative survey with a stratified multistage sampling design. Data from a comprehensive questionnaire, a physical examination, and blood tests were obtained from 5,844 Korean adults (2,513 men and 3,331 women) aged >20 years. RESULTS: The age-adjusted prevalence of diabetes in this Korean population was 7.6%, and the age-adjusted prevalences of previously diagnosed diabetes and newly diagnosed diabetes were 4.4 and 3.3%, respectively (fasting plasma glucose > or = 7.0 mmol/l). Overall, these results indicate that 8.1% or 1.4 million Korean men and 7.5% or 1.3 million Korean women have diabetes. The age-adjusted prevalence of IFG was 23.9%, using the new American Diabetes Association criteria (fasting plasma glucose 5.6-6.9 mmol/l). Diabetes prevalence increased with age and peaked in the oldest age-group; however, IFG prevalence did not show the same trend. Diabetes was found to be associated with age, BMI, blood pressure, triglyceride, HDL cholesterol, education levels, alcohol consumption, exercise, and a family history of diabetes. CONCLUSIONS: This study shows that diabetes and IFG are common in Korea, and about one-half of diabetes cases remain undiagnosed. These results emphasize the need to develop an urgent public program to improve the detection, prevention, and treatment of diabetes.

Adult↗
PubMedDate not supplied

[Fish species richness evaluation in Mexican coastal lagoons: a case study in the Gulf of Mexico].

We analyze the origin of knowledge about fish species richness in the Tuxpan-Tampamachoco estuarine system, in Veracuz, México. A complete inventory of the fish species known to date for this system (N = 179) was elaborated from published lists and from sampling seagrass meadows of Tampamachoco Lagoon, which yielded 14 previously unknown species. When compared, the different lists showed a low similarity that may reflect differences in sampling methods and collecting strategies. Current data suggest that fish species richness in Mexican coastal lagoons (Gulf of Mexico) is not related with lagoon surface area, as has been suggested, but with the number of inventories available for each lagoon, being these a reflection of the sampling effort. A sampling design for the assessment of fish species richness in estuarine systems should consider: a) using the highest possible variety of sampling fishing gears, b) collecting in all microhabitat types and c) the preference of bimonthly or quarterly samplings for two or more years over monthly samplings in a single year.

Animals↗
PubMed1984

The design of the Epidemiologic Catchment Area surveys. The control and measurement of error.

Several methods are used to minimize and measure error in the NIMH Epidemiologic Catchment Area program. Sampling methods involve the inclusion of group quarters such as prisons, nursing homes, and mental hospitals in the sample frame and the use of probability sampling throughout. Interviewing, methods include use of identical diagnostic interview protocols, centralized training of interview supervisors, standard instructions to interviewers, and reinterview of a subsample by clinicians. In the area of completion, the methods include a 75% to 80% respondent completion rate, a 95% or greater completion rate for individual questions, use of informant interviews where necessary, and statistical adjustments to correct for low completion rates in some subgroups. Analytic methods include use of a computerized diagnostic algorithm, common estimation formulas on identically formatted data files, and estimation of exact variances that take account of the multistage sample design.

Catchment Area, Health↗
PubMed2003

Implications of spatial heterogeneity for management of marine protected areas (MPAs): examples from assemblages of rocky coasts in the northwest Mediterranean.

Marine protected areas (MPAs) are increasingly used as a management tool to preserve species and habitats. Testing hypotheses about the effectiveness of MPAs is important for their implementation and to identify informative criteria to support management decisions. This study tested the general proposition that MPAs affected assemblages of algae and invertebrates between 0.0 and 0.5 m above the mean low water level of rocky coasts on two islands in the Tuscan Archipelago (northwest Mediterranean). Protection was concentrated mainly on the west coasts of the islands, raising the possibility that neither the full range of assemblages nor the relevant scales of variation were properly represented within MPAs. This motivated the comparison of assemblages on opposite sides of islands (habitats). The effects of MPAs and habitat were assessed with a multifactorial sampling design; hypotheses were tested about differences in structure of assemblages, in mean abundance of common taxa and in univariate and multivariate measures of spatial variation. The design consisted of three replicate shores for each condition of protected and reference areas on the west side of each island and three unprotected shores on the eastern side. Assemblages were sampled independently four times on each island between June 1999 and January 2001. At each time of sampling two sites were selected randomly at each of two tidal heights to represent midshore and lowshore assemblages on each shore. Estimates of abundance were obtained using non-destructive sampling methods from five replicate 20x20 cm quadrats at each site. Results indicated differences among habitats in structure of assemblages, in mean abundance of common taxa and in univariate and multivariate measures of spatial variation at the scale of shores. Most of these patterns were inconsistent with the predicted effect of management through MPAs. The data suggest that designation of MPAs in the Tuscan Archipelago should proceed through management of multiple shores and types of habitat selected to guarantee protection to a representative sample of assemblages and to the processes responsible for maintenance of spatial patchiness at different scales. This study also shows that considerations of spatial heterogeneity are important to underpin management decisions about the number, size and location of MPAs.

Animals↗