Disease relevance of Sample Size

• In addition, difficulties with data acquisition, such as substantial variabilities in serial measurements of percent diameter stenosis and minimal luminal diameters, require large sample sizes to show statistically significant regression, even with computerized quantification [1].
• The sample size was too small to determine whether warfarin had an effect on the incidence of silent infarction during the trial [2].
• The present study was undertaken with a larger sample size to determine whether the MTHFR 677C-->T polymorphism was associated with increased risk of having a child with Down syndrome [3].
• In contrast to postmenopausal breast cancer, a protective effect of dehydroepiandrosterone against premenopausal breast cancer is suggested, but because of the small sample size, the results of this study need to be replicated by others [4].
• A larger sample size is needed to determine whether ursodeoxycholic acid therapy has a beneficial effect on the survival of patients with primary biliary cirrhosis [5].

Psychiatry related information on Sample Size

• Because of small sample sizes and nonuniform determination of dementia, previous studies produced differing results on the influence of APOE subtypes on AD in DS [6].
• The sample sizes of these two pilot studies are too small to draw firm conclusions on the efficacy of flesinoxan in panic disorder, but the present data are not encouraging in this respect [7].
• Despite the small sample size, nefazodone significantly reduced some measures of alcohol consumption in this sample of depressed alcoholics [8].
• Health behavior and cortisol regulation, however, may require more sensitive measures and large sample sizes to discern their roles in loneliness and health [9].
• Although fluoxetine appears to be promising for the treatment of patients with anorexia nervosa, further studies need to be performed with a larger sample size and/or better design [10].

High impact information on Sample Size

• Little or no support was found for most reported IDDM loci (lods were less than 1), despite larger sample sizes in the present study [11].
• Future studies to identify the risk of cardiovascular events in women with PCOS will benefit from clear and extensive phenotyping of PCOS abnormalities at baseline, from a prospective design, from larger sample sizes, and from longer follow-up [12].
• In contrast to other estrogen receptor assays, this new technique requires a small sample size (about 5000 cells) and permits the assessment of heterogeneity in estrogen receptor expression among tumor cells [13].
• DATA EXTRACTION: Information on sample size, study drug duration, type and dosage of statin drug, participant characteristics at baseline, reduction in lipids during intervention, and outcomes was abstracted independently by 2 authors (J.H. and S.V.) using a standardized protocol [14].
• Although our sample size was small and type II error (false-negative trial) cannot be excluded, these data strongly suggest that prophylaxis with misoprostol does not prevent the acute gastroduodenal mucosal injury associated with hepatic arterial infusion of chemotherapeutic agents [15].

Chemical compound and disease context of Sample Size

• Heparin and aspirin in unstable angina: insufficient sample size may lead to erroneous conclusions [16].
• Although limited by uncontrolled design, small sample size and short duration, this study suggests that bosentan may benefit patients with PAH associated with HIV infection, and that endothelin is an important pathogenic mediator in this disease [17].
• Although the sample size of our study does not allow definite conclusions, these data are compatible with chronic tissue damage as a causative factor in the evolution of urothelial carcinomas rather than pointing to a direct mutagenic effect of phenacetin and tobacco-specific carcinogens [18].
• CONCLUSIONS: Although the results from our study suggest phytanic acid levels may be associated with prostate cancer risk, they were based on a study with a small sample size [19].
• Body weight and stool parameters in response to Sandostatin LAR Depot treatment needs to be assessed further in multicenter studies assessing dose, frequency of administration, and a larger sample size [20].

Biological context of Sample Size

• Stage I cases with DAP-kinase promoter methylation had worse overall survival, but with the small sample size and limited follow-up this did not reach statistical significance [21].
• The association of HER-2 genotype with clinicopathologic characteristics of gastric cancer was also suggested, which has to be confirmed with a larger sample size [22].
• CONCLUSIONS: This study suggested that a particular SLC6A4 haplotype harboring functional sequence variant could play a significant role in BPD etiology in Taiwan. However, due to its modest sample size, the conclusion is not final and should be confirmed in the future studies [23].
• HPLC techniques offer the advantage of tolerating lower sample purity, smaller sample size, and being dynamic range, compared with the flask-shaking method for measurement of logarithm of 1-octanol/water partition coefficients (log P), which is widely used in QSAR study [24].
• Genotyping by the TaqMan polymerase chain reaction method was performed for six missense or frameshift mutations and common single nucleotide polymorphisms in the general population, with a sample size of 1872 individuals (862 men and 1011 women) [25].

Anatomical context of Sample Size

• When added to the quantitative analysis of myocardial scintigraphy, the analysis of pulmonary thallium washout increased the detection of coronary artery disease from 84 to 93% (p less than 0.05), but the sample size was too small to assess specificity [26].
• With a randomized cross-over study design, the sample size predicted to be necessary to observe 50% attenuation of allergen-induced percent of eosinophils with a power of 0.95 was 5 subjects [27].
• Owing to the strict selection criteria and aseptic measures used, the low incidence of postoperative urinary tract infections in the control group (1.8 per cent) compared to none in the cefoperazone group made conclusions and generalization limited due to sample size [28].
• The applicability of the high-pressure liquid chromatographic assay to determination of diphenol oxidase activity in small biological sample sizes was demonstrated by using microgram quantities of crude, cell-free hemolymph from Aedes aegypti mosquitoes [29].
• We have extended our previous study by determining the frequency of HLA-DR-positive monocytes in the peripheral blood of well-defined groups of RP patients and by including a larger sample size of patients and subdividing the autosomal dominant and recessive subpopulations [30].

Associations of Sample Size with chemical compounds

• This report from the Stirling County Study compares rates of current depression among representative samples of adults from a population in Atlantic Canada. METHODS: Sample sizes were 1003, 1201, and 1396 in 1952, 1970, and 1992, respectively [31].
• Although arterial norepinephrine levels may be more sensitive than venous levels, venous levels do respond to stressors when attention is given to the time course of sampling, the imprecision of assays (and thus the requirement for larger sample sizes), and the selection of appropriate tasks [32].
• The limit of detection was less than one O6-alkyl-2'-deoxyguanosine in 10(7) 2'-deoxyguanosine residues in a sample size of 100 micrograms of DNA, i.e., approximately 10 pg of adduct [33].
• All the methods find significant differences between the alpha-difluoromethylornithine dose groups, but recommended sample sizes for a subsequent study are much smaller with the multivariate methods [34].
• However, small differences in the pattern of glucose utilization which might occur during late childhood and adolescence may not have been detected due to the sample size [35].

Gene context of Sample Size

• Previous reports that have assessed the association of GAD2 with type 1 diabetes have not used a dense map of markers surrounding the gene and have relied on very small clinical sample sizes [36].
• There was no apparent difference in the radiosensitivity between cells with BRCA1 vs. BRCA2 mutations (p = 0.769), although the small sample size minimizes the certainty of this observation [37].
• Thus, this study suggests that polymorphisms at MTHFR and a novel CYP1A1 variant could influence susceptibility to endometrial cancer, although larger sample sizes would be required to corroborate these findings [38].
• Although our observations regarding the age-dependent prognostic effects of TP53 and CDKN2A/p16 are consistent with a prior report regarding these alterations, the present results should be considered preliminary, given the small sample size [39].
• Given the large sample size, with more than adequate power to detect previously reported effects, we conclude that the AIB1 glutamine repeat does not substantially modify risk of breast cancer in BRCA1 and BRCA2 mutation carriers [40].

Analytical, diagnostic and therapeutic context of Sample Size

• The value of each of the three tests was then assessed by calculating (for each threshold) the numbers to be screened, the numbers requiring an OGTT, and the sample size of IGT subjects needed to detect a 33% reduction in NIDDM by an experimental intervention at a power of 80% [41].
• Importantly, the hypotheses were rejected despite the large sample size and sufficient statistical power.COMMENT: The most straight-forward clinical implication of this study is that acamprosate can be considered as a potentially effective pharmacotherapy for all patients with alcohol dependence [42].
• The outcomes of the fitting procedure were used to calculate sample sizes for future studies (duration, 6 months) using PSA increase over time in hormone-unresponsive prostate cancer as a marker for treatment efficacy [43].
• This value was then used to interpret the clinical significance of the results of published randomized controlled trials (RCTs) assessing the efficacy of tacrine in the treatment of AD and to retrospectively determine their optimal sample size and trial duration [44].
• Meta-analyses have been performed to overcome the small sample size of these trials, with the aim of assessing the benefit of amiodarone on total mortality [45].

References