Tag: statistics

Dtsch Arztebl Int. 2021 Sep 17;118(Forthcoming):arztebl.m2021.0224. doi: 10.3238/arztebl.m2021.0224.

ABSTRACT

BACKGROUND: The accurate diagnosis of a disease is a prerequisite for its appropriate treatment. How well a medical test is able to correctly identify or rule out a target disease can be assessed by diagnostic accuracy studies.

METHODS: The main statistical parameters that are derived from diagnostic accuracy studies, and their proper interpretation, will be presented here in the light of publications retrieved by a selective literature search, supplemented by the authors’ own experience. Aspects of study planning and the analysis of complex studies on diagnostic tests will also be discussed.

RESULTS: In the usual case, the findings of a diagnostic accuracy study are presented in a 2 × 2 contingency table containing the number of true-positive, true-negative, false-positive, and true-positive test results. This information allows the calculation of various statistical parameters, of which the most important are the two pairs sensitivity/specificity and positive/negative predictive value. All of these parameters are quotients, with the number of true positive (resp. true negative) test results in the numerator; the denominator is, in the first pair, the total number of ill (resp. healthy) patients, and in the second pair, the total number of patients with a positive (resp. negative) test. The predictive values are the parameters of greatest interest to physicians and patients, but their main disadvantage is that they can easily be misinterpreted. We will also present the receiver operating characteristic (ROC) curve and the area under the curve (AUC) as additional important measures for the assessment of diagnostic tests. Further topics are discussed in the supplementary materials.

CONCLUSION: The statistical parameters used to assess diagnostic tests are primarily based on 2 × 2 contingency tables. These parameters must be interpreted with care in order to draw correct conclusions for use in medical practice.

PMID:33975672 | DOI:10.3238/arztebl.m2021.0224

Fertil Steril. 2021 May 8:S0015-0282(21)00237-5. doi: 10.1016/j.fertnstert.2021.03.032. Online ahead of print.

ABSTRACT

OBJECTIVE: To compare neonatal and maternal outcomes among twin pregnancies conceived as a result of different types of fertility treatments with those of spontaneously conceived twin pregnancies.

DESIGN: Retrospective Cohort.

SETTING: Population-based analysis.

PATIENT(S): Population-based analysis of twin pregnancies in the United States based on their mode of conception using the natality data from the National Center for Health Statistics from the Centers for Disease Control and Prevention (from January 2015 through December 2017).

INTERVENTION(S): None.

MAIN OUTCOME MEASURE(S): Adverse neonatal and maternal outcomes.

RESULT(S): The overall prevalence of early adverse maternal outcomes and medical complications and obstetric complications including the risk of unplanned hysterectomy, intensive care unit admission, maternal blood transfusion, and perineal laceration were significantly higher in the fertility treatment group (including both ovulation induction/intrauterine insemination and assisted reproductive technology groups) compared with those of the spontaneous conception group, even after adjusting for several potential confounders. The risk of adverse composite neonatal outcomes was slightly lower in the spontaneous conception live twin birth group even after adjustment for several potential confounders.

CONCLUSION(S): The rate of maternal and neonatal morbidity in twins conceived via different fertility treatments was slightly increased compared with those of twins conceived spontaneously. Because the absolute risks of maternal and neonatal morbidity were low, overall reassurance regarding these outcomes can be provided to the patients undergoing all types of fertility treatments.

PMID:33975727 | DOI:10.1016/j.fertnstert.2021.03.032

Surgery. 2021 May 8:S0039-6060(21)00325-1. doi: 10.1016/j.surg.2021.03.062. Online ahead of print.

ABSTRACT

BACKGROUND: Surgical training has undergone many facets of restructuring over the most recent decades, with critiques of the quality and variability of training as well as the competency of recent graduates. This study examines the changes in surgical training in operative volume and breadth in the past 2 decades.

METHODS: The Accreditation Council for Graduate Medical Education Case Log Statistics Reports from 1999 to 2019 were reviewed. Case logs were grouped into defined case categories and group levels of postgraduate training. Descriptive analyses and multiple linear regressions were performed.

RESULTS: General surgery residents are graduating with 10.7% more cases, owing to increases in mostly junior year cases (P < .001). The breadth of specialty cases has decreased, while there was an increase in alimentary and abdominal cases to 58.4% from 47.2% 20 years ago. A decrease in vascular surgery cases from 19.9% to 10.7% of all cases was noted. Analysis of the distribution of defined categories showed right skewness in many categories with mode being much lower than reported mean.

CONCLUSION: Evaluation of trends, despite residents graduating with higher case volume than the minimum required, shows that the breadth and variety of cases has narrowed significantly in the past 20 years, providing a case for general surgery training restructuring.

PMID:33975730 | DOI:10.1016/j.surg.2021.03.062

Parasit Vectors. 2021 May 11;14(1):250. doi: 10.1186/s13071-021-04755-w.

ABSTRACT

BACKGROUND: Toxocariasis, caused by a nematode species of the genus Toxocara, has been described as one of the most prevalent zoonotic helminthiases worldwide. Human transmission may occur by ingesting Toxocara spp. larvae from raw or undercooked meat or organs; however, no comprehensive serosurvey study has been conducted to date investigating the role of cattle as paratenic hosts. The aim of the study reported here was to assess the prevalence of anti-Toxocara spp. antibodies and associated risk factors in bovines from two slaughterhouses located in Presidente Prudente, southeastern Brazil.

METHODS: Blood samples were collected and tested by indirect enzyme-linked immunosorbent assay (ELISA). Cattle farmers voluntarily responded to an epidemiologic questionnaire.

RESULTS: Overall, 213 of the 553 (38.5%) bovine samples were assessed as seropositive for anti-Toxocara spp. antibodies by indirect ELISA. Multivariate analysis revealed that the source of beef cattle and the presence of dogs or cats at the farm were associated with seropositivity. The use of feedlot systems was associated with lower likelihood of seropositivity.

CONCLUSIONS: These results indicate a high level of anti-Toxocara seropositivity in slaughterhouse cattle, with potentially contaminated meat posing an infection risk to humans. In addition, the presence of dogs and cats where the slaughtered beef cattle were raised was statistically associated with bovine seropositivity, probably due to the overlapping environment at the farm and the lack of pet deworming. The use of feedlot systems was a protective factor likely due to the absence of dog and cat contact, elevated feeding troughs that avoid contact with contaminated soil or grass, and younger age at slaughter of feedlot cattle. In summary, bovines may be used as environmental sentinels of Toxocara spp. contamination, and high seropositivity of slaughterhouse cattle may indicate a potential risk of human toxocariasis through the ingestion of raw or undercooked contaminated meat.

PMID:33975623 | DOI:10.1186/s13071-021-04755-w

Genome Biol. 2021 May 11;22(1):152. doi: 10.1186/s13059-021-02365-4.

ABSTRACT

Most research articles presenting new data analysis methods claim that “the new method performs better than existing methods,” but the veracity of such statements is questionable. Our manuscript discusses and illustrates consequences of the optimistic bias occurring during the evaluation of novel data analysis methods, that is, all biases resulting from, for example, selection of datasets or competing methods, better ability to fix bugs in a preferred method, and selective reporting of method variants. We quantitatively investigate this bias using an example from epigenetic analysis: normalization methods for data generated by the Illumina HumanMethylation450K BeadChip microarray.

PMID:33975646 | DOI:10.1186/s13059-021-02365-4

Cardiooncology. 2021 May 11;7(1):17. doi: 10.1186/s40959-021-00103-0.

ABSTRACT

BACKGROUND: The CBR3 V244M single nucleotide polymorphism has been linked to the risk of anthracycline-related cardiomyopathy in survivors of childhood cancer. There have been limited prospective studies examining the impact of CBR3 V244M on the risk for anthracycline-related cardiotoxicity in adult cohorts.

OBJECTIVES: This study evaluated the presence of associations between CBR3 V244M genotype status and changes in echocardiographic parameters in breast cancer patients undergoing doxorubicin treatment.

METHODS: We recruited 155 patients with breast cancer receiving treatment with doxorubicin (DOX) at Roswell Park Comprehensive Care Center (Buffalo, NY) to a prospective single arm observational pharmacogenetic study. Patients were genotyped for the CBR3 V244M variant. 92 patients received an echocardiogram at baseline (t_{0 month}) and at 6 months (t_{6 months}) of follow up after DOX treatment. Apical two-chamber and four-chamber echocardiographic images were used to calculate volumes and left ventricular ejection fraction (LVEF) using Simpson’s biplane rule by investigators blinded to all patient data. Volumetric indices were evaluated by normalizing the cardiac volumes to the body surface area (BSA).

RESULTS: Breast cancer patients with CBR3 GG and AG genotypes both experienced a statistically significant reduction in LVEF at 6 months following initiation of DOX treatment for breast cancer compared with their pre-DOX baseline study. Patients homozygous for the CBR3 V244M G allele (CBR3 V244) exhibited a further statistically significant decrease in LVEF at 6 months following DOX therapy in comparison with patients with heterozygous AG genotype. We found no differences in age, pre-existing cardiac diseases associated with myocardial injury, cumulative DOX dose, or concurrent use of cardioprotective medication between CBR3 genotype groups.

CONCLUSIONS: CBR3 V244M genotype status is associated with changes in echocardiographic parameters suggestive of early anthracycline-related cardiomyopathy in subjects undergoing chemotherapy for breast cancer.

PMID:33975650 | DOI:10.1186/s40959-021-00103-0

BMC Health Serv Res. 2021 May 11;21(1):449. doi: 10.1186/s12913-021-06472-7.

ABSTRACT

BACKGROUND: County hospitals as the backbone of the China’s healthcare system are providing services for over 70% of the total population. However, the hospital management practice (HMP) and its links with quality of care, efficiency and finance in these hospitals are unknown.

METHODS: We did two cross-sectional surveys of HMP in 2013 and 2015 among 101 county hospitals across rural China. Three managing roles (hospital director, director of medical affairs office and director of cardiology) and a cardiologist were invited to the surveys. A novel HMP rating scale, with 100 as full score, was used to measure the HMP in 17 indicators under four dimensions (target, operation, performance, and talent management) for each hospital. We analyzed the association of HMP score with variables on quality of care, efficiency and finance using linear mixed models with and without adjustment for potential confounders.

FINDINGS: A total of 95 hospitals participated in at least one survey and were included in the analysis. The overall mean HMP score varied dramatically across the hospitals and 84% of them scored less than 60. The dimension mean HMP score was 38.6 (target), 56.4 (operation), 53.2 (performance) and 55.7 (talent), respectively. The pattern of indicator mean HMP score, however, was almost identical between hospitals with high and low overall HMP score, showing the same ‘strength’ (staff satisfaction, staff performance appraisal, ‘hard wares’, patient-centered services, etc.) and ‘weakness’ (target balance, target setting, continuous quality improvement, penalties on staff with dissatisfied performance, etc.). The associations of overall mean HMP score with quality of care and efficiency variables and cost per hospitalization was not statistically significant. The statistical significance in the association with hospital annual total income disappeared after adjusting for region, teaching status, number of competitors, number of staff and number of beds in use.

CONCLUSION: The HMP in Chinese county hospitals scores low in general and was not significantly associated with hospital care quality, efficiency and finance. The current healthcare reform in China should address the micro level issues in hospital management practices.

PMID:33975605 | DOI:10.1186/s12913-021-06472-7

Undersea Hyperb Med. 2021 Second-Quarter;48(2):149-152.

ABSTRACT

Middle ear barotrauma (MEB) is a common complication of hyperbaric oxygen (HBO2) therapy. It has been reported in more than 40% of HBO2 treatments and can interrupt the sequence of HBO2. MEB may lead to pain, tympanic membrane rupture, and even hearing loss. The aim of this study was to determine if pretreatment with intranasal fluticasone and oxymetazoline affected the incidence of MEB. We conducted a retrospective chart review of subjects undergoing HBO2 at our institution between February 1, 2014, and May 31, 2019. Subjects in the fluticasone/oxymetazoline (FOT) treatment group used intranasal fluticasone 50 mcg two times per day and oxymetazoline 0.05% one spray two times per day beginning 48 hours prior to initial HBO2. Oxymetazoline was discontinued after four days. Fluticasone was continued for the duration of HBO2 therapy. A total of 154 unique subjects underwent 5,683 HBO2 treatments: 39 unique subjects in the FOT group underwent 1,501 HBO2; 115 unique subjects in the nFOT (no oxymetazoline or fluticasone treatment) group underwent 4,182 HBO2 treatments. The incidence of MEB was 15.4% in the FOT group and 16.2% in the nFOT group. This was not a statistically significant difference (OR = 0.77; p = 0.636). Treatment pressure, age over 65 years, male sex, and BMI were not associated with a difference in MEB incidence. In summary, pretreatment with intranasal oxymetazoline and fluticasone in patients undergoing HBO2 did not significantly reduce MEB. More investigation with larger numbers of participants and prospective studies could further clarify this issue.

PMID:33975404

J Obstet Gynaecol Res. 2021 May 11. doi: 10.1111/jog.14829. Online ahead of print.

ABSTRACT

AIM: To evaluate the efficacy and safety of ureteral stent placement (USP) as a preoperative procedure for gynecological cancer surgeries.

METHODS: This was a single-institution retrospective cohort study of 259 patients with gynecological cancer who underwent laparotomy. In 126 patients (USP+ group), a ureteral stent was inserted into the bilateral ureters after the induction of general anesthesia. The remaining 133 patients (USP- group) did not undergo USP. We compared operation time, blood loss, and frequency of laparotomy-related perioperative urinary complications between the groups. The stent was removed 5-7 days postoperatively. Patients were evaluated for signs of hydronephrosis at discharge. The Fisher’s exact test was used to investigate the significance of differences in patient characteristics, and multivariate analysis was performed using a Cox proportional hazards model. A p-value of <0.05 was considered statistically significant.

RESULTS: There were no significant differences in age and body mass index between the groups. Two patients in the USP- group experienced intraoperative ureteral injury. Total operation time and blood loss were significantly increased in the USP+ group. The risk of bladder tamponade and postoperative hydronephrosis was influenced by USP. USP was unaffected by a history of abdominal surgery, stage of tumor progression, lymphadenectomy type, or hysterectomy type.

CONCLUSIONS: The incidence of bladder tamponade and hydronephrosis postoperatively was significantly higher in patients with USP than in those without USP.

PMID:33975384 | DOI:10.1111/jog.14829

J Korean Med Sci. 2021 May 10;36(18):e125. doi: 10.3346/jkms.2021.36.e125.

ABSTRACT

BACKGROUND: We aimed to investigate the annual incidence of trauma and stress-related mental disorder including acute stress disorder (ASD) and post-traumatic stress disorder (PTSD) using the National Health Insurance Service Database. In addition, we estimated direct medical cost of ASD and PTSD in Korea.

METHODS: To examine the incidence, we selected patients who had at least one medical claim containing a 10th revision of the International Statistical Classification of Diseases and Related Health Problems code for ASD (F43.0) and PTSD (F43.1) and had not been diagnosed in the previous 360 days, from 2010 to 2017. We estimated annual incidence and the number of newly diagnosed patients of ASD and PTSD. Annual prevalence and direct medical cost of ASD and PTSD were also estimated.

RESULTS: The number of newly diagnosed cases of ASD and PTSD from 2011 to 2017 totaled 38,298 and 21,402, respectively. The mean annual incidence of ASD ranged from 8.4 to 13.7 per 100,000 population and that of PTSD ranged from 4.2 to 8.3 per 100,000 population, respectively. The incidence of ASD was found more in females and was highest among the 70-79 years of age group and the self-employed individuals group. The incidence of PTSD was also more common in the female group. However, the incidence of PTSD was highest in the 60-69 years of age group and in the medical aid beneficiaries group. The annual estimated medical cost per person of ASD ranged from 104 to 149 US dollars (USD). In addition, that of PTSD ranged from 310 to 426 USD.

CONCLUSION: From 2011 to 2017, the annual incidence and direct medical cost of ASD and PTSD in Korea were increased. Proper information on ASD and PTSD will not only allows us to accumulate more knowledge about these disorders themselves but also lead to more appropriate therapeutic interventions by improving the ability to cope with these trauma related psychiatric sequelae.

PMID:33975398 | DOI:10.3346/jkms.2021.36.e125