PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “summary statistics”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed1999

Summary statistics for acute cardiac ischemia and chest pain visits to United States EDs, 1995-1996.

In this article we describe characteristics of emergency encounters for patients with a diagnosis of acute cardiac ischemia (ACI) and for patients with chest pain complaints. Data are from the National Hospital Ambulatory Medical Care Survey, which includes abstracts from the medical records of a national probability sample of visits to emergency departments (ED). Analysis was limited to records of patients 25 years of age and older with a diagnosis of either confirmed or suspected acute myocardial infarction (AMI) or unstable angina pectoris and records with a nontraumatic chest pain complaint. There was an estimated annual average of 1.2 million visits to EDs by patients 25 years and over with a diagnosis of ACI in 1995-1996, an average annual rate of 7.2 visits per 1,000 persons. Visit rates varied by patient's age, race, and gender. Chest pain was a complaint in three-fourths of all ACI visits. There were an estimated 4.6 million annual ED visits where in patients aged 25 years and older had complaints of nontraumatic chest pain, an average annual rate of 27.7 visits per 1,000 persons. ACI accounted for 11% of all chest pain visits, but the probability of the chest pain visit having an ACI diagnosis varied by patient's age and race. There remains a large amount of variation in treatment for suspected and confirmed AMI, and for patients presenting with chest pain to EDs.

Adult↗
PubMed2006

A summary statistic approach to sequence variation in noncoding regions of six schizophrenia-associated gene loci.

In order to explore the role of noncoding variants in the genetics of schizophrenia, we sequenced 27 kb of noncoding DNA from the gene loci RAC-alpha serine/threonine-protein kinase (AKT1), brain-derived neurotrophic factor (BDNF), dopamine receptor-3 (DRD3), dystrobrevin binding protein-1 (DTNBP1), neuregulin-1 (NRG1) and regulator of G-protein signaling-4 (RGS4) in 37 schizophrenia patients and 25 healthy controls. To compare the allele frequency spectrum between the two samples, we separately computed Tajima's D-value for each sample. The results showed a smaller Tajima's D-value in the case sample, pointing to an excess of rare variants as compared to the control sample. When randomly permuting the affection status of sequenced individuals, we observed a stronger decrease of Tajima's D in 2400 out of 100,000 permutations, corresponding to a P-value of 0.024 in a one-sided test. Thus, rare variants are significantly enriched in the schizophrenia sample, indicating the existence of disease-related sequence alterations. When categorizing the sequenced fragments according to their level of human-rodent conservation or according to their gene locus, we observed a wide range of diversity parameter estimates. Rare variants were enriched in conserved regions as compared to nonconserved regions in both samples. Nevertheless, rare variants remained more common among patients, suggesting an increased number of variants under purifying selection in this sample. Finally, we performed a heuristic search for the subset of gene loci, which jointly produces the strongest difference between controls and cases. This showed a more prominent role of variants from the loci AKT1, BDNF and RGS4. Taken together, our approach provides promising strategy to investigate the genetics of schizophrenia and related phenotypes.

Brain-Derived Neurotrophic Factor↗
PubMed1997

A summary statistic for measuring change from baseline.

A statistic, W, for measuring change from baseline is developed. Its distribution is found. Simulations using W and analysis of covariance (ANCOVA) are run and the results are compared. W is found to be less powerful than ANCOVA, yet is not seen to suffer some of the ill effects to which ANCOVA can fall prey, namely bias introduced by chance covariate imbalance.

Analysis of Variance↗
PubMed1988

Patients on Warrants of the Lieutenant Governor in Alberta: a statistical summary with comments on treatment and release procedures.

Files on all 48 Alberta patients under Warrants of the Lieutenant Governor were reviewed in late 1984, early 1985. Few were on Warrant as a result of unfitness to stand trial and all carried a primary diagnosis involving major mental disorder. More than half were considered paranoidal. Two-thirds of the population had killed someone or attempted to do so. Only eight had not previously been inpatients in psychiatric hospitals. Nearly half of the patients offended against relatives. Close to two-thirds had a previous criminal record. The Alberta Hospital's Forensic Service is described as is the province's Board of Review. Two brief case studies help portray the system of gradual release. The authors comment on the design of services for this group of patients known to be hard to treat and administer.

Adult↗
PubMed2002

Summary statistics for pediatric psychiatric visits to US emergency departments, 1993-1999.

OBJECTIVES: To describe characteristics of emergency department (ED) encounters for pediatric patients with an acute mental health diagnosis. METHODS: Data are from the National Hospital Ambulatory Medical Care Survey, which includes abstracts from the medical records of a national probability sample of visits to EDs. Analysis was limited to records of patients who were younger than 19 years and had a diagnosis of either confirmed or suspected mental disorder or a suicide attempt. RESULTS: There was an estimated annual average of 434 000 ED pediatric mental health visits from 1993 to 1999, an average annual rate of 326.8 visits per 10 000 people. Visit rates varied by patient's region, age, race, and gender. Psychosis was the diagnosis in 10.8% of these patients, and suicide attempt was the diagnosis in 13.6%. ED pediatric mental health visits accounted for 1.6% of all ED visits in this age group. CONCLUSIONS: The significant increase in emergency department pediatric mental health (EDPMH) visits from 1993-1999 is greatest among patients who are non-white, teenaged, female, and live in the Northeast or Midwest. This variation in EDPMH visits may reflect variability in the shortage of mental health providers. The lack of increase in the 2 categories of diagnoses mandatorily seen in EDs--psychoses and suicide attempts--suggests that the overall rise in EDPMH visits may have been attributable to nonurgent complaints more appropriately managed by a primary mental health provider.

Adolescent↗
PubMed2001

Formulas for combining summary statistics.

Formulas for computing the combined mean and standard deviation for any number of groups are presented. These formulas produce results that are different from the pooling (averaging) method.

Humans↗