Misuse and Artifact in Factor Analytic Research

The theory of factor analysis has been developed for incorporating mathematical　statistical theories such as the maximum likelihood method and asymptotic methods. However, there have been several instances of misuse while employing procedures for factor analysis studies. In several studies, factor analysis has been performed by deleting items exhibiting the ceiling effect or floor effect. The number of samples required for factor analysis is not well known. Kaiser-Guttman criterion cannot be applied for determining the number of factors. Furthermore, various studies have employed Scree Graphs and Parallel Analysis for the said purpose, but no definitive method exists for the same. Orthogonal rotation methods such as Varimax cannot be considered as a conclusive solution. However, Geomin has been considered as a better rotation method not only for simple structure but also for more complex factor configuration. Simple structure and bifactor structure are discussed in connection to factor rotation problem. Although there are various artifacts associated with the usage of factor analysis, this issue can be addressed by verifying factorial invariance through multi-group simultaneous analysis incorporated by SEM programs such as Mplus and R Package.因子分析の理論は、最尤法と漸近的方法のような数理統計学的理論を組み込んだ形で発展してきた。しかしながら、因子分析研究の手順にはまだ誤用がみられる。いくつかの研究において、天井効果や床効果を示す項目を削除して因子分析が行われている。因子分析に必要なサンプル数は明確ではない。因子の数を決定するためにKaiser-Guttman 基準は使うことはできない。そして、この目的でScree Graph とParallel Analysis を使用している研究は数多くあるが、そのための決定的な方法はない。Varimax のような直交回転は最終的な解と考えることはできない。しかしながら、Geomin は単純構造だけでなくより複雑な因子の布置に対しても優れた回転方法と考えられている。因子回転問題を考慮した単純構造とbifactor 構造について議論した。因子分析の使い方には多くのartifacts があるが、この問題は、Mplus やR Package などのSEMプログラムによって組み込まれた複数集団の同時分析によって因子的不変性を検証することによって対処することができる

COVID-19: New scenario old problems

The short paper present the problem of hospital acquired infection in subintensive units of a research and teaching hospital

A spatiotemporal reconstruction of the 1630 plague epidemic in Milan

In 1630, a devastating plague epidemic struck Milan, one of the most important Italian cities of that time, deeply affecting its demography and economy for decades. The lack of digitized historical data strongly limits our comprehension of that important event. In this work, we digitized and analyzed the Milan death registers of 1630. The study revealed that the epidemic evolved differently among the areas of the city. Indeed, we were able to group the parishes of the city (comparable with modern neighborhoods) in two groups based on their epidemiological curves. These different epidemiological progressions could reflect socio-economical and/or demographic features specific of the neighborhoods, opening questions about the relationship between these features and the evolution of epidemics in the pre-modern period. The study of historical records, like the one presented here, can help us to better understand European history and pre-modern epidemics

Analysis of circulating extracellular vesicle-associated microRNAs in cortisol-producing adrenocortical tumors

PURPOSE: Circulating microRNAs (miRNA) have been described in patients with adrenocortical tumors, but the expression of miRNAs in non-functioning and cortisol-producing tumors has not been yet compared. Therefore, the objective of this study was to evaluate the expression of plasma extracellular vesicle (EV)-associated microRNAs in patients with non-functioning adrenocortical adenoma (NFA), cortisol-producing adrenocortical adenoma (CPA) and cortisol-producing adrenocortical carcinoma (CP-ACC). METHODS: Preoperative plasma EV samples of 13 NFAs, 13 CPAs and 9 CP-ACCs were subjected to extracellular vesicle isolation. miRNAs were investigated by targeted quantitative real-time PCR normalized to cel-miR-39 as reference. Five miRNAs have been selected for this analysis based on the previous studies including hsa-miR-22-3p, hsa-miR-27a-3p, hsa-miR-210-3p, hsa-miR-320b and hsa-miR-375. RESULTS: We have observed significant overrepresentation of three miRNAs in both CPA and CP-ACC relative to NFA: hsa-miR-22-3p (p < 0.01 and p < 0.0001, respectively), hsa-miR-27a-3p (p < 0.05 in both comparisons) and hsa-miR-320b (p < 0.05 and p < 0.0001, respectively). Hsa-miR-320b has been significantly overrepresented in CP-ACC relative to CPA (p < 0.01). Hsa-miR-210-3p turned out to be significantly overrepresented only in CP-ACC compared to NFA (p < 0.05). Significant correlation was revealed between circulating miRNA concentrations and urinary free cortisol values for hsa-miR-22-3p, hsa-miR-27a-3p and hsa-miR-320b (p < 0.0001 for all) and cortisol after low-dose dexamethasone test for hsa-miR-22-3p and hsa-miR-320b (p < 0.05). Hsa-miR-27a-3p has been significantly stimulated by low-dose dexamethasone test (p < 0.05). CONCLUSIONS: EV-associated miRNAs are differentially expressed in different non-functioning and cortisol-producing adrenocortical tumors

Assessing Lifestyle in a Large Cohort of Undergraduate Students: Significance of Stress, Exercise and Nutrition

Background/Objectives: Lifestyle (in particular, nutrition and exercise) determines present and future youths’ health. The goal of the present study was to identify specific student groups who deserve precise lifestyle improvement interventions, tailored to their characteristics. Methods: An anonymous web-based questionnaire to assess lifestyle was posted on the websites of two main Italian Academic Institutions, and 9423 students voluntarily participated. A personalised immediate report was provided to improve compliance/motivation. We assessed age, sex, affiliation, anthropometrics, lifestyle components (nutrition, exercise, sedentariness, stress perception, smoking, alcohol, sleep), and the desire to be helped with lifestyle improvement. Cluster analysis was performed to identify healthy lifestyle groups among the students. Results: In total, 6976 subjects [age: 21 (20,23) yrs; 3665 female, 3300 male] completed the questionnaire and were included. Of these students, 73.9% expressed the need for lifestyle improvement help, particularly for becoming physically active (66.7%), managing stress (58.7%), and improving nutrition (52.7%). We unveil three clusters of subjects, each corresponding to a distinct lifestyle pattern. The clusters are differentiated by exercise level and perceptions of stress/fatigue/somatic symptoms (cluster 1: 74.8% meet international exercise guidelines (IEGs), 67.4% have high stress perception, 49.1% drink 1–3 glasses of wine/beer per week, and 63.3% drink 0–1 glass of spirits per week; cluster 2: 75.6% meet IEGs, 75.7% have low/medium levels of stress perception, and 65.8% have low alcohol consumption; cluster 3: 72.5% do not meet IEGs, 77.6% have high stress perception, and 67.5% have low alcohol consumption). More active students present lower stress/somatic symptoms perception. Interestingly, the AHA diet score (nutrition quality) was not in the ideal range in any cluster (nevertheless, obesity was not of concern), being worst in cluster 3, characterized by higher stress perception (59.7% had poor nutrition quality). Those who were physically active but showed a high stress/fatigue perception were used to drinking alcohol. Conclusions: Students desire help to improve their lifestyle, and this approach might help identify specific student groups to whom LIs in Academic Institutions can be tailored to foster well-being and promote health

The development and testing of balanced communication material for a population-based breast cancer screening program

Organized breast cancer screening (BCS) programs rely on written communication materials for achieving participation and informing women about screening-related benefits and limits. In order to achieve informed decisions and to maximize reader acceptance, the Agency for Health Protection of the metropolitan area of Milan aimed at improving the communication materials of the local BCS program through a multiphase, mixed-method process. Multidisciplinary working groups drafted three sets of materials: postal letters, an informative leaflet, and a question-and-answer online set. Readability was assessed using the Italian language-tailored Gulpease index. Suitability and Comprehensibility were assessed using the SAM + CAM instrument. User perception was investigated through "think aloud"interviews in two consecutive purposive samples. Participants' intention to participate in the program was also assessed. After each phase was completed, materials were readapted, and previous phases were repeated, to maintain the pre-defined Gulpease and SAM + CAM targets. During the quality improvement process, the overall mean Gulpease and SAM + CAM scores increased from 65.5 (s. d. 10.4) to 67.7 (s. d. 8.2) and from 78 (s. d. 5.6) to 83 (s. d. 4.1), respectively. In light of the results of the first round of interviews, materials underwent rewriting and layout revision, which was generally appreciated during the second round, with a non-significant increase in the intention to participate in the program. However, negative emotions and miscomprehension concerning overdiagnosis were frequently reported, although less frequent in the second round, after rewording of the text. The mixed-method multistep process involving all the relevant key players allowed a balance among the multifaceted aspects of communication

Prognostic and monitoring value of circulating tumour cells in adrenocortical carcinoma: a preliminary monocentric study.

Adrenocortical carcinoma (ACC), a rare and aggressive neoplasia, presents poor prognosis when metastatic at diagnosis and limited therapies are available. Specific and sensitive markers for early diagnosis and a monitoring system of therapy and tumor evolution are urgently needed. The liquid biopsy represents a source of tumor material within a minimally invasive blood draw that allows the recovery of circulating tumor cells (CTCs). CTCs have been recently shown to be detectable in ACC. In the present paper, we evaluated the prognostic value of CTCs obtained by size-filtration in a small pilot cohort of 19 ACC patients. We found CTCs in 68% of pre-surgery and in 38% of post-surgery blood samples. In addition, CTC clusters (CTMs) and cancer associated macrophages (CAMLs) were detectable in some ACC patients. The median number of CTCs significantly decreased after the mass removal. Finally, stratifying patients in high and low pre-surgery CTC number groups, assuming the 75th percentile CTC value as cut-off, CTCs significantly predicted patients&rsquo; overall survival (log rank = 0.005), also in a multivariate analysis adjusted for age and tumor stage. In conclusion, though preliminary and performed in a small cohort of patients, our study suggests that CTC number may represent a promising marker for prognosis and disease monitoring in ACC

Screening of women with aesthetic prostheses in dedicated sessions of a population-based breast cancer screening programme

Background: Women with aesthetic prostheses must be included in the target population of mammography screening programmes. Breast implants are radiopaque and partially obscure the breast tissue. This can be avoided with the use of the Eklund technique, which causes an increased radiation exposure. In this study, augmented women undergoing a dedicated protocol within a population-based screening programme were compared according to selected indicators with the standard screening population. Essential dosimetric parameters and their time trend were also assessed. Materials and methods: The study was conducted in a screening centre in Milan in the years 2009–2016. The screening protocol for women with breast implants included a double-read mammography with the Eklund views, ultrasound and clinical breast examination. Results: A total of 28,794 women were enrolled, including 588 (2%) women with breast implants and 28,206 (98%) undergoing the standard screening protocol. The invasive assessment rate was 9.0‰ for women with breast implants vs. 15‰ in the standard cohort. The surgical referral rate was 2.2% vs. 0.9%. The detection rate was similar in the two groups (4.0 and 4.5‰, respectively). There were significant differences in the average glandular dose according to the mammography equipment. The use of the Eklund views increased over time. Conclusions: Screening of augmented women according to a specific protocol in the contexts of population-based programmes is feasible. Observed differences in screening indicators relative to the standard screening population require further research. The increasing use of Eklund views probably results from quality assurance measures associated with screening programmes