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PubMed2002

D-cycloserine for Alzheimer's disease.

BACKGROUND: Evidence supports a role for the NMDA receptors in learning and memory. These can be modulated by the antibiotic D-cycloserine in such a way that the effect of the excitatory transmitter substance glutamate is enhanced. A study on healthy subjects pretreated with scopolamine to mimic Alzheimer's disease showed a positive effect of D-cycloserine at low doses. OBJECTIVES: To assess the efficacy and safety of D-cycloserine in patients with Alzheimer's disease. SEARCH STRATEGY: The trials were identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 14 June 2001 using the terms: cycloserine, D-cycloserine, Alzheimer*. SELECTION CRITERIA: Randomized, double-blinded and unconfounded trials comparing D-cycloserine with a control treatment. DATA COLLECTION AND ANALYSIS: Two larger and two smaller randomized controlled trials were identified. The clinical global impression scale was used in all studies and was a primary outcome measure. MAIN RESULTS: It was not possible to extract the results from the first phases of the two crossover studies and therefore the meta-analyses are based on the two parallel group 6-month studies. There was no indication of a positive effect favouring D-cycloserine for the numbers showing improvement at 6 months as assessed by the Clinical Global Impression for any dose. The number of withdrawals for any reason before end of treatment at 6 months was significantly in favour of placebo (fewer withdrawals) compared with D-cycloserine for dose levels of 30 mg/day (OR 2.94, 95% CI 1.52, 5.70) and 100 mg/day (OR 3.23, 95% CI 1.67, 6.25). There was no significant difference between treatment, (2, 10, 30, 100, or 200 mg/day) and placebo for the number of withdrawals due to adverse events by six months. REVIEWER'S CONCLUSIONS: The lack of a positive effect of D-cycloserine on cognitive outcomes in controlled clinical trials with statistical power high enough to detect a clinically meaningful effect means that D-cycloserine has no place in the treatment of patients with Alzheimer's disease.

Alzheimer Disease↗
PubMed2004

Intramuscular arteether for treating severe malaria.

BACKGROUND: Quinine and artemisinin drugs are used in severe malaria, but quinine resistance is increasing. Arteether is a recently developed artemisinin derivative that is oil soluble, has a long elimination half life, and is more stable than other derivatives. OBJECTIVES: To compare intramuscular arteether with other antimalarial drugs to treat severe malaria. SEARCH STRATEGY: We searched the Cochrane Infectious Diseases Group Specialized Register (August 2004), CENTRAL (The Cochrane Library Issue 3, 2004), MEDLINE (1966 to August 2004), EMBASE (1980 to August 2004), U.S. National Library of Medicine (NLM) Gateway (1953 to 1965), Web Science Citation (1981 to August 2004), LILACS (August 2004), Google search engine (August 2004), conference proceedings, and reference lists. We also contacted researchers, organizations, and pharmaceutical companies to help identify trials. SELECTION CRITERIA: Randomized and quasi-randomized controlled trials of intramuscular arteether in adults and children with severe malaria. DATA COLLECTION AND ANALYSIS: We independently assessed the methodological quality of the trials and extracted data, and analysed data using Review Manager 4.2. MAIN RESULTS: Two small trials (n = 194) met the inclusion criteria. Both trials compared arteether with quinine in children with cerebral malaria and reported on similar outcomes. There was no statistically significant difference in the number of deaths (relative risk 0.75, 95% confidence interval 0.43 to 1.30; n = 194, 2 trials), neurological complications (relative risk 1.18, 95% confidence interval 0.31 to 4.46; n = 58, 1 trial), or other outcomes including time to regain consciousness, parasite clearance time, and fever clearance time. The meta-analyses lack statistical power to detect important differences. REVIEWERS' CONCLUSIONS: More trials with a larger number of participants are needed before a firm conclusion about the efficacy and safety of arteether can be reached.

Adult↗
PubMed2006

Probiotics for maintenance of remission in Crohn's disease.

BACKGROUND: Crohn's disease (CD) is characterised by episodes of disease activity and symptom-free remission. Probiotics are microorganisms that can potentially benefit health, and have been evaluated as an alternate means of preventing relapse in patients with CD. OBJECTIVES: To assess the effectiveness of probiotics for the maintenance of remission in CD. SEARCH STRATEGY: The following databases were searched: the Cochrane Database of Systematic Reviews (2005, Issue 3); the Cochrane Central Register of Controlled Trials (2005, Issue 3); the Cochrane IBD/FBD Group Trials Register (2005), MEDLINE (1966-2005); EMBASE (1980-2005); ISI Web of Knowledge (BIDS) 1981-2005; On-line clinical trials databases (2005); and review articles. Experts in the field were contacted for unpublished data. SELECTION CRITERIA: Randomised controlled trials of probiotic therapy. DATA COLLECTION AND ANALYSIS: Two independent reviewers performed data extraction and assessment of methodological quality. The primary outcome was the relative risk (RR) of relapse after maintenance treatment (and 95% confidence intervals [CI]). MAIN RESULTS: Seven small studies were identified and varied according to probiotics tested, methodological quality and medication regimen. No studies were pooled for statistical analysis. There was no statistically significant benefit of E. coli Nissle for reducing the risk of relapse compared to placebo (RR 0.43, 95% CI 0.15 to 1.20), or Lactobacillus GG after surgically-induced remission (RR 1.58, 95% CI 0.30 to 8.40) or medically-induced remission (RR 0.83, 95% CI 0.25 to 2.80). There was no statistically significant benefit of probiotics for reducing the risk of relapse compared to maintenance therapy employing aminosalicylates or azathioprine (RR 0.67, 95% CI 0.13 to 3.30), and in this study the probiotic Lactobacillus GG was associated with adverse events. In children, there was there was no statistically significant difference between Lactobacillus GG and placebo for reducing the risk of relapse (RR 1.85, 95% CI 0.77 to 4.40). A small study using the yeast Saccharomyces boulardii demonstrated a difference that was not statistically significant in favour of probiotic combined with a reduced level of maintenance therapy over standard maintenance treatment alone (RR 0.17, 95% CI 0.02 to 1.23). AUTHORS' CONCLUSIONS: There is no evidence to suggest that probiotics are beneficial for the maintenance of remission in CD. All of the included studies enrolled small numbers of patients and may have lacked statistical power to show differences should they exist. Larger trials are required to determine if probiotics are of benefit in Crohn's disease.

Adult↗
PubMed2006

Dehydroepiandrosterone (DHEA) supplementation for cognitive function in healthy elderly people.

BACKGROUND: In view of the theoretical possibility of beneficial effects of DHEA or DHEAS in retarding age-associated deterioration in cognitive function, we have reviewed studies in this area. OBJECTIVES: To establish whether administration of DHEA, or its sulphate, DHEAS, improves cognitive function or reduces the rate of decline of cognitive function in normal older adults. SEARCH STRATEGY: Trials were identified from a last updated search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 10 October 2005 using the terms dhea*, prasterone, dehydroepiandrosterone*. In addition MEDLINE, EMBASE, PsycINFO and CINAHL were searched to find trials with volunteers who had no or minor memory complaints. Relevant journals, personal communications and conference abstracts were searched for randomized controlled trials investigating the effects of DHEA/S on cognition in older adults. SELECTION CRITERIA: All randomized placebo-controlled trials enrolling people aged over 50 without dementia and to whom DHEA/S in any dosage was administered for more than one day were considered for inclusion in the review. DATA COLLECTION AND ANALYSIS: Data for the specified outcomes were independently extracted by two reviewers (JGE and RM) and cross-checked. Any discrepancies were discussed and resolved. No data pooling was undertaken owing to the lack of availability of the relevant statistics. MAIN RESULTS: Only three studies provided results from adequate parallel-group data. Barnhart 1999 enrolled perimenopausal women with complaints of decreased well-being and, using three cognitive measures, found no significant effect of DHEA compared with placebo at 3 months. Wolf 1998b enrolled 75 healthy volunteers (37 women and 38 men aged 59-81) in a study of the effect of DHEA supplements on cognitive impairment induced by stress; after two weeks of treatment, placebo group performance deteriorated significantly on a test of selective attention following a psychosocial stressor (p<0.05), while deterioration was not evident in the DHEA group (p=0.85). However, when compared with placebo, DHEA was associated with a significant impairment on a visual memory recall test (p<0.01) following the stressor. No significant effects were found on a third cognitive task. Effects were not found on tasks when administered in the absence of a stressor. van Niekerk 2001 found no effect on cognitive function in 46 men aged 62-76 from three months of DHEA supplementation. DHEA supplements were well tolerated and without significant adverse effects apart from the reduced performance in the visual memory recall test observed in one trial. AUTHORS' CONCLUSIONS: What little evidence there is from controlled trials does not support a beneficial effect of DHEA supplementation on cognitive function of non demented middle-aged or elderly people. There is no consistent evidence from the controlled trials that DHEA produces any adverse effects. In view of growing public enthusiasm for DHEA supplementation, particularly in the USA, and the theoretical possibility of long-term neuroprotective effects of DHEA/S, there is a need for further high quality trials in which the duration of DHEA treatment is longer than one year, and the number of participants is large enough to provide adequate statistical power.

Aged↗
PubMedDate not supplied

Apolipoproteins (apoproteins) and LPL variation in Mennonite populations of Kansas and Nebraska.

Apoproteins (also known as apolipoproteins) have been studied extensively because of their role in lipid transport, association between specific genotypes and elevated serum lipid levels, and increased risk of heart disease. There is considerable genetic variation in the geographic distributions of these markers, with a north-south cline of the APOE*4 allele observed in Europe by Lucotte et al. ([1997] Hum Biol 69:253-262). This study compares the frequencies of seven APO (APOA1 -75 bp, APOA1 +83 bp, APOB Ins/Del, APOB XbaI, APOC3 SstI, and APOE) and LPL loci in Mennonite populations from Kansas and Nebraska. In total, 277 individuals were sampled from Goessel, Meridian, Garden View, and Lone Tree in 2002-2004. In addition, DNA samples that were collected in 1981 from Henderson, Nebraska, were genotyped for the seven APO and LPL loci. Of the seven APO and LPL loci tested, only one locus, APOB XbaI, departed significantly from Hardy-Weinberg equilibrium, with an unexpected excess of observed heterozygotes. The frequencies of the several APO loci are unique among the Mennonites, separating them from other European populations. A bidimensional scaling representation of Reynold's co-ancestry distances based on allelic frequencies of the seven APO and LPL markers in five Mennonite congregations fails to represent schematically the known patterns of fission. It is unclear whether the observed patterns are due to selection operating on these loci or whether genetic drift, small populations sizes, or a lack of statistical power of these biallelic loci distort the observed genetic relationship among congregations.

Apolipoproteins↗
PubMed2001

Nested case-control analysis of high pesticide exposure events from the Agricultural Health Study.

BACKGROUND: A nested case-control analysis of high pesticide exposure events (HPEEs) was conducted using the Iowa farmers enrolled in the Agricultural Health Study (AHS). METHODS: In the 12 months of the study, 36 of the 5,970 farmer applicators randomly chosen from the AHS cohort (six per 1,000 farmer applicators per year) met our definition of an HPEE, by reporting "an incident with fertilizers, weed killers, or other pesticides that caused an unusually high personal exposure" resulting in physical symptoms or a visit to a health care provider or hospital. Eligibility criteria were met by 25 HPEE cases and 603 randomly selected controls. RESULTS: Significant risk factors for an HPEE included: poor financial condition of the farm which limited the purchase of rollover protective structures OR = 4.6 (1.5-16.6), and having a high score on a risk acceptance scale OR = 3.8 (1.4-11.2). Other non-significant factors were also identified. CONCLUSIONS: The limited statistical power of this study necessitates replication of these analyses with a larger sample. Nonetheless, the observed elevated odds ratios of an HPEE provide hypotheses for future studies that may lead to preventive action.

Accidents, Occupational↗
PubMed2006

Lung cancer mortality among workers at a nuclear materials fabrication plant.

BACKGROUND: The Oak Ridge, Tennessee Y-12 plant has operated as a nuclear materials fabrication plant since the 1940s. Given the work environment, and prior findings that lung cancer mortality was elevated among white male Y-12 workers relative to US white males, we investigated whether lung cancer mortality was associated with occupational radiation exposures. METHODS: A cohort of 3,864 workers hired between 1947 and 1974 who had been monitored for internal radiation exposure was identified. Vital status was ascertained through 1990. RESULTS: Over the study period 111 lung cancer deaths were observed. Cumulative external radiation dose under a 5-year lag assumption was positively associated with lung cancer mortality (0.54% increase in lung cancer mortality per 10 mSv, se=0.16, likelihood ratio test (LRT)=5.84, 1 degree of freedom [df]); cumulative internal radiation dose exhibited a highly-imprecise negative association with lung cancer mortality. DISCUSSION: The positive association between external radiation dose and lung cancer mortality was primarily due to exposure occurring in the period 5-14 years after exposure (0.97% increase in lung cancer mortality rate per 10 mSv, se=0.28, LRT=6.35, 1 df). The association between external radiation dose and lung cancer mortality was negative for exposures occurring at ages<35 years and positive for exposures occurring at ages 35-50 and 50+years. CONCLUSIONS: There is evidence of a positive association between cumulative external radiation dose and lung cancer mortality in this population. However, a causal interpretation of this association is constrained by the uncertainties in external and internal radiation dose estimates, the lack of information about exposures to other lung carcinogens, and the limited statistical power of the study.

Adult↗
PubMed1984

Survey of reproductive hazards among oil, chemical, and atomic workers exposed to halogenated hydrocarbons.

Several halogenated hydrocarbons are suspected of causing adverse reproductive effects. Because of such concerns, the Oil, Chemical, and Atomic Workers International Union surveyed the reproductive histories of two groups of workers. One group worked at plants engaged in the production or use of halogenated hydrocarbons (exposed) whereas the others had no such opportunity for exposure (nonexposed). Although a low response rate precludes firm conclusions, the 1,280 completed questionnaires provide useful data for generating hypotheses in this developing field of interest. A history of diagnosed cancer was reported more frequently among exposed workers. The infant mortality rate was also significantly elevated among the offspring of exposed workers. No risk gradient was observed for episodes of infertility, fetal loss, congenital defects, or low-birthweight offspring. Concerns with nonresponse, exposure characterization, possible confounding factors, and limited statistical power are addressed. The results provide further suggestions which help to direct studies of occupational reproductive risks.

Abnormalities, Drug-Induced↗
PubMed1985

Mortality patterns among styrene-exposed boatbuilders.

In order to test the hypothesis that leukemia and lymphoma may be associated with exposure to styrene, cause-of-death patterns were studied at two reinforced plastic boatbuilding facilities. There were 5,021 workers who met the criterion of having worked at the two plants between 1959 and 1978. Based on industrial hygiene surveys conducted at the two plants, 2,060 individuals were determined to have worked in departments classified as having high exposure to styrene. There were 176 deaths observed among the total cohort, in comparison to 195.3 deaths expected (standardized mortality ratio [SMR] = 90). Among the high styrene exposure group, 47 deaths were observed in comparison to 41.5 deaths expected (SMR = 113). No leukemia or lymphoma deaths were observed in either the high exposure group or the total cohort. An excess of accidental deaths among the high exposure group (18 observed vs 12.4 expected) did not appear to be due to styrene's acute central nervous system effects, since none of the individuals were employed at the facilities at the time of their death. However, the possibility of a chronic effect could not be dismissed. While leukemia and lymphoma did not appear to be related to styrene exposure, the study had little statistical power to detect excesses of these diseases, due to the short length of observation and the young age of most cohort members. It was concluded that the cohort should provide increasingly useful information on chronic styrene toxicity as the population ages and the observation period increases.

Adolescent↗
PubMed1987

Nasal cancer in the U.S. shoe industry: does it exist?

Studies in England and Italy have demonstrated a striking association between employment in the shoemaking industry and cancer of the nasal cavities and sinuses. However, three recent, large-scale proportionate mortality studies of U.S. shoeworkers do not show any deaths from these tumors. This paper reviews the methodology of those studies, emphasizing the underlying data and statistical power. In addition, epidemiologic and other considerations important in assessing and interpreting the apparent absence of a nasal cancer risk in the U.S. shoe industry are discussed.

Cross-Sectional Studies↗
PubMed1989

Asbestos and kidney cancer: the evidence supports a causal association.

The role of asbestos in the etiology of lung cancer and of mesothelioma of the pleura and peritoneum has been well documented. The evidence for a causal association between asbestos and other human cancers is not as extensive but suggests that asbestos may be carcinogenic at several different sites. This paper is concerned specifically with a possible causal association between asbestos and human kidney cancer. A review of the evidence to date indicates that only three human studies have sufficient statistical power to detect an excess mortality from kidney cancer among workers exposed to asbestos. All three were occupational cohort studies, and two of these gave strong direct evidence for such an excess; a study of U.S. insulators (kidney cancer SMR = 2.22, 90% CI 1.44-3.30), and a study of U.S. asbestos products company workers (kidney cancer SMR = 2.76, 90% CI 1.29-5.18). The third study, of Italian shipyard workers, reported excess mortality from "cancers of the kidney, urinary bladder, and other urinary organs" (SMR = 1.98, 90% CI 1.42-2.70). Further support for a causal association includes studies finding asbestos fibers in human kidneys and urine, as well as reports of kidney tumors in two animal bioassays. It is concluded that asbestos should be regarded as a probable cause of human kidney cancer.

Animals↗
PubMed1992

A study of the cardiac effects of bromochlorodifluoromethane (halon 1211) exposure during exercise.

Bromochlorodifluoromethane (halon 1211, a fire extinguisher), like other fluorocarbons, has been linked with ventricular arrhythmias and myocardial depression. Ten healthy firefighters, aged 40-50, were exposed to 1,000 ppm halon while exercising, in a double-blind, placebo-controlled crossover experiment, and were monitored during and after exposure. Complex ectopy (ventricular couplets and idioventricular rhythm) occurred in two subjects with halon, but none with placebo. One subject had 49.5 ventricular premature beats (VPB)/hour during the period of halon exposure and subsequent 8 hours and only 8.7 VPB/hour during the same period of placebo. In addition, 8 of the 10 subjects had a smaller systolic blood pressure rise during exercise with halon than with placebo. None of the observed differences was statistically significant. These results are consistent with findings in other investigations, suggesting that occupational fluorocarbon exposures may be cardiotoxic in certain individuals, although the small sample sizes used in this and other studies have resulted in limited statistical power to demonstrate this effect.

Adult↗
PubMed1994

Mortality and cancer morbidity of Finnish chlorophenoxy herbicide applicators: an 18-year prospective follow-up.

An 18-year follow-up for mortality and cancer morbidity was conducted in a cohort of 1,909 men who had started spraying chlorophenoxy herbicides (mixture of 2,4-dichlorophenoxyacetic acid [2,4-D] and 2,4,5-trichlorophenoxyacetic acid [2,4,5-T]) in 1955 through 1971. In all, 384 persons had died during the follow-up, and there was a slight deficit in natural deaths (standardized mortality ratio [SMR] 0.84; 95% confidence interval [CI] 0.75-0.94). By contrast, there was a small, nonsignificant increase in accidental and violent deaths. The overall cancer mortality was slightly less than in the general population (SMR 0.83; 95% CI 0.65-1.02), and not a single case of death of non-Hodgkin's lymphomas (NHL) or soft tissue sarcomas (STS) was detected. With regard to cancer morbidity, the incident cases showed a slight deficit compared to the population figure (standardized incidence ratio [SIR] 0.81; 95% CI 0.67-0.97). One case of NHL was found (2.4 expected with 10 years of latency), but not a single case of STS (0.8 expected with 10 years of latency). While our study does not support the contention that spraying of 2,4-D and 2,4,5-T containing herbicides carries any significant risk of cancer, the medium to low statistical power of the study does not allow any far reaching negative conclusions regarding the carcinogenicity of the agents.

2,4,5-Trichlorophenoxyacetic Acid↗
PubMed1994

Epidemiological studies of work with video display terminals and adverse pregnancy outcomes (1984-1992).

Many epidemiological studies have investigated the claim that work with video display terminals (VDT) is a risk factor during pregnancy. Results have been inconsistent, although in the majority of cases the hypothesis was not supported. Exposure assessment has been very poor and the statistical power of the studies generally low. Overall, the studies indicate that VDT operators are not at greater risk than the general population, because very low frequency (VLF) magnetic fields do not appear to be a risk factor and extremely low frequency (ELF) magnetic field exposure is not significantly greater than that experienced in other occupational and residential environments. However, since some studies lend support to the hypothesis that ELF magnetic fields may be a risk factor for pregnancy outcome, studies of subjects exposed to higher than average ELF fields are justified.

Abortion, Spontaneous↗
PubMed2002

Lack of association of a single-nucleotide polymorphism of the mu-opioid receptor gene with anxiety-related traits: results from a cross-sectional study of adults and a longitudinal study of children.

There is evidence from animal experiments that the mu- and delta-opioid receptors may play a role in anxiety and depression. It might therefore be expected that functional polymorphisms of these genes in humans are associated with anxiety and depression. We investigated a single-nucleotide polymorphism (Asn40Asp) of the mu-opioid receptor gene (OPRM1). This association was investigated in two samples: 1) a cross-sectional survey of 867 community-living adults aged 18-79 years who were assessed for anxiety and depression symptoms and related personality traits; and 2) a longitudinal study of childhood temperament in which 660 children were followed from infancy to the mid-teens and assessed for anxiety-related temperament and behavior problems. The data did not support a role for the Asn40Asp polymorphism in anxiety and depression, despite adequate statistical power to detect small effects.

Adolescent↗
PubMed2002

Genetic loci for pathological myopia are not associated with juvenile myopia.

The purpose of this study was to evaluate chromosomal regions previously linked to pathological myopia for linkage to juvenile myopia in a sample of myopic children and their families. Of 125 families with a myopic child participating in the Orinda longitudinal study of myopia, 53 submitted 221 buccal swab samples for genetic analysis. Myopia in proband children was defined as -0.75 D or more myopia in both meridians on cycloplegic autorefraction (1% tropicamide). Affected status in parents and siblings was obtained by survey. DNA was extracted from buccal mucosal cells, amplified by polymerase chain reaction (PCR), and then analyzed with seven markers for chromosome 12 and five markers for chromosome 18 in the regions previously associated with pathological myopia. LOD scores were not significant for any marker tested. The largest positive LOD score was 0.15 for GATA30F04. Model-free methods using a SimIBD approach suggested a possible linkage at one marker, GATA6H09 (P = 0.003), but these results were not supported by transmission disequilibrium test (TDT) analysis. The statistical power to detect LOD scores of > or =1.0, assuming homogeneity, was estimated at 93.2%. We found no confirmatory evidence of linkage between juvenile myopia and regions of chromosomes 12 and 18 previously associated with pathological myopia.

Child↗
PubMed1986

DUCHEN: an interactive computer program for calculating heterozygosity (carrier) risks in X-linked recessive lethal diseases, and its application in Duchenne muscular dystrophy.

The program DUCHEN calculates the probability that a woman is a carrier of an X-linked, lethal recessive disease on the basis of information in the woman's family and any available biochemical data. It is easily used by persons without computer knowledge or experience. The present version can accommodate families consisting of up to 100 people in seven generations. Risks may be estimated on the basis of pedigree information only, or with the inclusion of one or more types of biochemical test results. Biochemical data are incorporated with pedigree information into final risks using the powerful statistical technique of logistic discrimination, a procedure particularly suited for the separation of non-normal populations on the basis of overlapping quantitative characteristics. Mutation rates are specified separately for males and females. DUCHEN is available in FORTRAN 77, IBM BASIC, and Applesoft BASIC, and may be used on a variety of mainframe or microcomputers. The model was used to calculate risks for 375 girls and women in 46 families with Duchenne muscular dystrophy (DMD); serum creatine kinase tests had been carried out on 167 of these subjects who were of reproductive age. Carrier probabilities equal to or lower than the population risk (0.0004) were obtained for 21% of the aunts and 43% of the cousins of affected boys from families with an isolated case of DMD and for 14% of the cousins of affected boys from families with a known DMD history. DUCHEN should assist counsellors in determining which members of large families should be further examined using either standard biochemical carrier detection methods or DNA marker studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Creatine Kinase↗
PubMed1989

Autism is not associated with the fragile X syndrome.

We provided a controlled test of the hypothesis that individuals with the Martin-Bell or Fragile X [fra(x)] syndrome are more autistic than mentally retarded control individuals. A sample of fra(x) individuals was obtained from the register of a clinical genetics unit and compared with mentally retarded control individuals selected from an assessment centre who were individually matched for age, sex, and IQ. A comparison of 45 pairs of fra(x) cases and control individuals on the DSM-III (R) criteria for autism and two standardized "instruments" for the assessment of autism (ABC and ADC) failed to find a higher prevalence of autism among fra(x) individuals. There was no statistically significant difference between fra(x) individuals and control individuals, and the mean differences on both the ABC and ADC scales were in the direction contrary to the hypothesis. An analysis of the study's statistical power suggested that it is unlikely the investigation failed to detect a large to medium difference between fra(x) individuals and control individuals in autistic behaviour. Subsidiary analyses of case-control differences showed that two autistic-like behaviours occurred at a higher rate among fra(x) individuals than other mentally retarded children, namely, gaze avoidance and hand flapping. These abnormalities may have misled clinicians into thinking that autism and fra(x) are associated.

Adolescent↗