PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Factor Analysis, Statistical”

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
PubMedDate not supplied

Retrospective statistical analysis of factors influencing the formation of long-term complications following hallux abducto valgus surgery.

A retrospective analysis was performed to determine the long-term results of hallux abducto valgus surgery done under the auspices of the Texas Health Science Center at San Antonio and its teaching hospitals. Two hundred eighty-five patients with a postoperative follow-up ranging from 3 to 10 years were studied. Attempts were made to study many of the patient demographic factors and perioperative procedures that acted to affect the development of a long-term complication. It was found that type of procedure, past medical history, age, medical control, and location of the surgical suite were all important variables to consider in this regard.

Adolescent↗
PubMed2001

Perceptions of body image, happiness and satisfaction in adolescents wearing a Boston brace for scoliosis treatment.

AIMS: To explore the impact of bracing on the perceptions of body image, happiness and satisfaction of adolescents with scoliosis. DESIGN: The study was designed as compare of 134 girls and 16 boys who wore a Boston type brace for scoliosis treatment and a control group of 99 healthy girls and 51 healthy boys. All them were secondary school pupils living in Athens Greece and were interviewed. A semi-structured schedule included general questions, and the Piers-Harris scale was used. Data were analysed using the SPSS/PC+ software, and descriptive statistics, factor analysis and the non-parametric Mann-Whitney U-test. Statistical significance was set at P=0.05 or less. RESULTS: The scoliosis group had a poorer perception of body image in comparison to the control group (P=0.048), while boys with scoliosis (P=0.030) had a better perception of body image than girls with scoliosis. Girls with scoliosis had a statistically significant difference (P=0.0388) in perception of happiness and satisfaction, in comparison with girls in the control group. Cohabitation with the mother seemed to be negatively correlated with body image, happiness and satisfaction perceptions because adolescents with scoliosis who were not living with their mother had a better body image perception (P=0.027) as well as better perceptions of happiness and satisfaction (P=0.047). Nevertheless, only 5% of those with scoliosis declared that they had opportunities to discuss their feelings and problems with health professionals, while 90% of them declared that they wanted to have more opportunities to do this. CONCLUSION: Adolescents with scoliosis face problems during bracing and they need to be supported by health care professionals.

Adolescent↗
PubMed2005

Reliability of the Thai-modified Function Living Index Cancer questionnaire version 2 (T-FLIC 2) for the evaluation of quality of life in non-small cell lung cancer patients.

Quality of life is an important measurement of medical outcome. The objective of the present study was to determine the reliability and validity of the Thai-Modified Function Living Index Cancer questionnaire version 2 (T-FLIC 2) in Non-Small Cell Lung Cancer (NSCLC) patients. The FLIC was developed into Thai version 2 and applied to a sample of 36 in-patients with NSCLC. Reliability was assessed by internal consistency using the Cronbach's alpha statistic, and validity was checked by construct validity using the factor analysis statistic. Cronbach's alpha coefficient, equal to 0.8710, showed good reliability. A factor analysis was conducted to examine construct validity. It revealed a 5-factor solution accounting for 58.075 percent of the variance. In conclusion, the T-FLIC 2 is a reliable and valid measurement of the quality of life in NSCLC patients and can be used in clinical trials, studies of outcome and research in oncology.

Adult↗
PubMed2002

Pain catastrophizing and general health status in a large Dutch community sample.

The aim of the present study was to examine the association between pain catastrophizing and general health status in a Dutch adult community sample, including various subgroups of people with musculoskeletal pain in the analyses. For exploratory reasons this study partly replicated previous studies of the factor structure, reliability, and validity of the Pain Catastrophizing Scale (PCS). Results demonstrated that across different pain subgroups, catastrophizing uniquely contributed variance to the prediction of the various aspects of general health status beyond the variance explained by pain intensity, age, gender, and chronicity. Across subgroups strongest associations were found between catastrophizing and mental health, general health perception, social functioning, and vitality. Furthermore, the association between catastrophizing and the various aspects of general health status was not moderated by the chronicity of the pain. Results of the confirmatory factor analysis statistically confirmed a three-factor model of the PCS, which was invariant across different subgroups of people with musculoskeletal pain. Inter-factor correlations were high, and the incremental explanatory power of the three-factor model over that of a one-factor model was only marginal. This implies that a one-factor model might be justifiable as well, at least in the general community. Across various pain subgroups the reliability of the PCS total and subscales was adequate. Additional evidence for the concurrent validity of the PCS was found as well.

Adult↗
PubMed2001

In common batch searching of illicit heroin samples--evaluation of data by chemometrics methods.

In this study three illicit heroin samples which belonged to three different batches were subdivided into eight samples each. To simulate the dealers' chain, and to check the influence (if any) of diluents on the analytical results, some of the samples were cut with the most frequently used cutting substances, whereas the others were left unchanged. Samples were analysed (within a 10-week period of time) by gas chromatography-mass spectrometry (GC-MS) and characterised by seven variables each. To recover batch links among investigated heroin samples three multivariate methods, i.e. hierarchical clustering (HCA), principal component analysis (PCA) and k-nearest neighbours (k-NN), were applied on to the normalised and scaled analytical dataset. The classification abilities of the HCA, PCA and k-NN were in the range from 95 to 100%. Disturbing effects due to the dilution of samples have not been observed.

Analysis of Variance↗
PubMedDate not supplied

[PASS neurocognitive dysfunction in attention deficit].

INTRODUCTION: Attention deficit disorder shows both cognitive and behavioral patterns. OBJECTIVE: To determine a particular PASS (planning, attention, successive and simultaneous) pattern in order to early diagnosis and remediation according to PASS theory. PATIENTS AND METHODS: 80 patients were selected from the neuropediatric attendance, aged 6 to 12 years old, 55 boys and 25 girls. Inclusion criteria were inattention (80 cases) and inattention with hyperactive symptoms (40 cases) according to the Diagnostic and Statistical Manual (DSM-IV). Exclusion criteria were the criteria of phonologic awareness previously reported, considered useful to diagnose dyslexia. A control group of 300 individuals, aged 5 to 12 years old, was used, criteria above mentioned being controlled. DN:CAS (Das-Naglieri Cognitive Assessment System) battery, translated to native language, was given to assess PASS cognitive processes. Results were analyzed with cluster analysis and t-Student test. Statistical factor analysis of the control group had previously identified the four PASS processes: planning, attention, successive and simultaneous. RESULTS: The dendrogram of the cluster analysis discriminated three categories of attention deficit disorder: 1. The most frequent, with planning deficit; 2. Without planning deficit but with deficit in other processes, and 3. Just only a few cases, without cognitive processing deficit. Cognitive deficiency in terms of means of scores was statistically significant when compared to control group (p = 0.001). CONCLUSIONS: According to PASS pattern, planning deficiency is a relevant factor. Neurological planning is not exactly the same than neurological executive function. The behavioral pattern is mainly linked to planning deficiency, but also to other PASS processing deficits and even to no processing deficit.

Attention↗
PubMed2005

Studentized maximum root procedures for coherent analyses of two-factor fixed-effects designs.

The authors provide generalizations of R. J. Boik's (1993) studentized maximum root (SMR) procedure that allow for simultaneous inference on families of product contrasts including simple effect contrasts and differences among simple effect contrasts in coherent analyses of data from 2-factor fixed-effects designs. Unlike the F-based simultaneous test procedures (STPs) proposed by M. A. Betz and K. R. Gabriel (1978) for coherent analyses allowing for inferences on all factorial contrasts, SMR STPs are designed for analyses where each contrast of interest is a product contrast, which is usually the case in analyses of data from factorial experiments. When both factors have more than 2 levels, SMR STPs always provide more power and precision than F STPs for inferences on product contrasts.

Analysis of Variance↗
PubMed2006

Profiling local optima in K-means clustering: developing a diagnostic technique.

Using the cluster generation procedure proposed by D. Steinley and R. Henson (2005), the author investigated the performance of K-means clustering under the following scenarios: (a) different probabilities of cluster overlap; (b) different types of cluster overlap; (c) varying samples sizes, clusters, and dimensions; (d) different multivariate distributions of clusters; and (e) various multidimensional data structures. The results are evaluated in terms of the Hubert-Arabie adjusted Rand index, and several observations concerning the performance of K-means clustering are made. Finally, the article concludes with the proposal of a diagnostic technique indicating when the partitioning given by a K-means cluster analysis can be trusted. By combining the information from several observable characteristics of the data (number of clusters, number of variables, sample size, etc.) with the prevalence of unique local optima in several thousand implementations of the K-means algorithm, the author provides a method capable of guiding key data-analysis decisions.

Algorithms↗
PubMedDate not supplied

Profile of non communicable disease risk factors in an industrial setting.

AIM: The profile of non communicable diseases (NCD) risk factors was identified in an industry by pre tested WHO's STEPS questionnaire. SETTINGS AND DESIGN: A cross-sectional survey of all employment categories of an Industry (2000 employees) was done after randomly selecting subjects (220) from worker (52%) and non worker categories (47.4%), after informed consent. MATERIALS AND METHODS: Information was collected on behavioural risk factors (STEP I), followed by anthropometric and blood pressure measurements by a trained investigator (STEP II). STEP III constituted biochemical assessment of "at risk" subjects (> 3 risk factors). STATISTICAL ANALYSIS: Percentage of subjects having NCD risk factors and the odds ratios were calculated. RESULTS: Overall risk factor profile of the study subjects revealed universal prevalence of 3 risk factors) with prevalence of hypercholesterolemia, hypertension and diabetes of 40.5, 38.2 and 19.1% respectively. CONCLUSIONS: A high prevalence of NCD risk factors in industrial setting was seen; therefore public health approaches are required at workplace settings to curtail the rising epidemic in the productive populations.

Adult↗