Category: Statistics

JMIR Form Res. 2022 Apr 18;6(4):e28091. doi: 10.2196/28091.

ABSTRACT

BACKGROUND: The rising prevalence of gestational diabetes mellitus (GDM) calls for the use of innovative methods to inform and empower these pregnant women. An information chatbot, Dina, was developed for women with GDM and is Norway’s first health chatbot, integrated into the national digital health platform.

OBJECTIVE: The aim of this study is to investigate what kind of information users seek in a health chatbot providing support on GDM. Furthermore, we sought to explore when and how the chatbot is used by time of day and the number of questions in each dialogue and to categorize the questions the chatbot was unable to answer (fallback). The overall goal is to explore quantitative user data in the chatbot’s log, thereby contributing to further development of the chatbot.

METHODS: An observational study was designed. We used quantitative anonymous data (dialogues) from the chatbot’s log and platform during an 8-week period in 2018 and a 12-week period in 2019 and 2020. Dialogues between the user and the chatbot were the unit of analysis. Questions from the users were categorized by theme. The time of day the dialogue occurred and the number of questions in each dialogue were registered, and questions resulting in a fallback message were identified. Results are presented using descriptive statistics.

RESULTS: We identified 610 dialogues with a total of 2838 questions during the 20 weeks of data collection. Questions regarding blood glucose, GDM, diet, and physical activity represented 58.81% (1669/2838) of all questions. In total, 58.0% (354/610) of dialogues occurred during daytime (8 AM to 3:59 PM), Monday through Friday. Most dialogues were short, containing 1-3 questions (340/610, 55.7%), and there was a decrease in dialogues containing 4-6 questions in the second period (P=.013). The chatbot was able to answer 88.51% (2512/2838) of all posed questions. The mean number of dialogues per week was 36 in the first period and 26.83 in the second period.

CONCLUSIONS: Frequently asked questions seem to mirror the cornerstones of GDM treatment and may indicate that the chatbot is used to quickly access information already provided for them by the health care service but providing a low-threshold way to access that information. Our results underline the need to actively promote and integrate the chatbot into antenatal care as well as the importance of continuous content improvement in order to provide relevant information.

PMID:35436213 | DOI:10.2196/28091

JMIR Aging. 2022 Apr 15;5(2):e36825. doi: 10.2196/36825.

ABSTRACT

BACKGROUND: Early detection of dementia is critical for intervention and care planning but remains difficult. Computerized cognitive testing provides an accessible and promising solution to address these current challenges.

OBJECTIVE: The aim of this study was to evaluate a computerized cognitive testing battery (BrainCheck) for its diagnostic accuracy and ability to distinguish the severity of cognitive impairment.

METHODS: A total of 99 participants diagnosed with dementia, mild cognitive impairment (MCI), or normal cognition (NC) completed the BrainCheck battery. Statistical analyses compared participant performances on BrainCheck based on their diagnostic group.

RESULTS: BrainCheck battery performance showed significant differences between the NC, MCI, and dementia groups, achieving 88% or higher sensitivity and specificity (ie, true positive and true negative rates) for separating dementia from NC, and 77% or higher sensitivity and specificity in separating the MCI group from the NC and dementia groups. Three-group classification found true positive rates of 80% or higher for the NC and dementia groups and true positive rates of 64% or higher for the MCI group.

CONCLUSIONS: BrainCheck was able to distinguish between diagnoses of dementia, MCI, and NC, providing a potentially reliable tool for early detection of cognitive impairment.

PMID:35436212 | DOI:10.2196/36825

J Med Internet Res. 2022 Apr 15;24(4):e29380. doi: 10.2196/29380.

ABSTRACT

BACKGROUND: In obesity management, whether patients lose ≥5% of their initial weight is a critical factor in clinical outcomes. However, evaluations that take only this approach are unable to identify and distinguish between individuals whose weight changes vary and those who steadily lose weight. Evaluation of weight loss considering the volatility of weight changes through a mobile-based intervention for obesity can facilitate understanding of an individual’s behavior and weight changes from a longitudinal perspective.

OBJECTIVE: The aim of this study is to use a machine learning approach to examine weight loss trajectories and explore factors related to behavioral and app use characteristics that induce weight loss.

METHODS: We used the lifelog data of 13,140 individuals enrolled in a 16-week obesity management program on the health care app Noom in the United States from August 8, 2013, to August 8, 2019. We performed k-means clustering with dynamic time warping to cluster the weight loss time series and inspected the quality of clusters with the total sum of distance within the clusters. To identify use factors determining clustering assignment, we longitudinally compared weekly use statistics with effect size on a weekly basis.

RESULTS: The initial average BMI value for the participants was 33.6 (SD 5.9) kg/m², and it ultimately reached 31.6 (SD 5.7) kg/m². Using the weight log data, we identified five clusters: cluster 1 (sharp decrease) showed the highest proportion of participants who reduced their weight by >5% (7296/11,295, 64.59%), followed by cluster 2 (moderate decrease). In each comparison between clusters 1 and 3 (yo-yo) and clusters 2 and 3, although the effect size of the difference in average meal record adherence and average weight record adherence was not significant in the first week, it peaked within the initial 8 weeks (Cohen d>0.35) and decreased after that.

CONCLUSIONS: Using a machine learning approach and clustering shape-based time series similarities, we identified 5 weight loss trajectories in a mobile weight management app. Overall adherence and early adherence related to self-monitoring emerged as potential predictors of these trajectories.

PMID:35436211 | DOI:10.2196/29380

Curr Microbiol. 2022 Apr 18;79(6):163. doi: 10.1007/s00284-022-02854-0.

ABSTRACT

The present study was an attempt to evaluate the bio-formulations of phosphate-solubilizing fungus Aspergillus awamori S29 using two economically viable carriers (calcium alginate and agar) in repeated batch fermentation. Further, the viable cell count under storage and response of these stored bio-formulations on the growth of wheat plants were studied at the end of 2, 4, and 6 months of incubation. Also, the response of these formulations in next season on pearl millet (bajra) was studied without further inoculation. In repeated batch fermentation assay, immobilized form performed significantly better than free form. The viability of fungal inoculant was 88.2% in calcium alginate-based bio-formulation after six months of storage. These bio-formulations showed not only a statistically significant increase in the growth of wheat crop in first season but also of pearl millet in next season. This work strengthens the re-usability potential of immobilized bio-formulations for next season crop.

PMID:35435528 | DOI:10.1007/s00284-022-02854-0

Acta Neurochir (Wien). 2022 Apr 18. doi: 10.1007/s00701-022-05190-1. Online ahead of print.

ABSTRACT

PURPOSE: To externally validate the arteriovenous malformation-related intracerebral haemorrhage (AVICH), intracerebral haemorrhage (ICH), and novel haemorrhage presentation risk score (R2eD) in brain arteriovenous malformations.

METHODS: Adult patients diagnosed radiologically with an arteriovenous malformation (AVM) at a tertiary neurosurgical centre between 2007 and 2018 were eligible for inclusion. Both the AVICH and ICH scores were calculated for AVM-related symptomatic haemorrhage (SH) and compared against the modified Rankin scale (mRS) at discharge and last follow-up, with unfavourable outcome defined as mRS > 2. R2eD scores were stratified based on presentation with SH. External validity was assessed using Harrel’s C-statistic.

RESULTS: Two hundred fifty patients were included. Mean age at diagnosis was 46.2 years [SD = 16.5]). Eighty-seven patients (34.8%) had a SH, with 83 included in the analysis. Unfavourable mRS outcome was seen in 18 (21.6%) patients at discharge and 18 (21.6%) patients at last follow-up. The AVICH score C-statistic was 0.67 (95% confidence interval [CI], 0.53-0.80) at discharge and 0.70 (95% CI, 0.56-0.84) at last follow-up. The ICH score C-statistic was 0.78 (95% CI 0.67-0.88), at discharge and 0.80 (95% CI 0.69-0.91) at last follow-up. The R2eD score C-statistic for predicting AVM haemorrhage was 0.60 (95% CI, 0.53-0.67).

CONCLUSIONS: The AVICH score showed fair-poor performance, while the ICH score showed good-fair performance. The R2eD score demonstrated poor performance, and its clinical utility in predicting AVM haemorrhage remains unclear.

PMID:35435515 | DOI:10.1007/s00701-022-05190-1

Eur Spine J. 2022 Apr 18. doi: 10.1007/s00586-022-07215-w. Online ahead of print.

ABSTRACT

OBJECTIVE: To determine the effect of endplate reduction on the final healing morphology and degenerative changes in intervertebral discs.

METHODS: Forty-eight patients with single-level thoracolumbar fractures with endplate injury were included. All patients underwent posterior reduction and pedicle screw fixation, and postoperative imaging was used to determine whether endplate reduction was successful. The healing morphology of the endplate was divided into three types: increased endplate curvature, irregular healing and traumatic Schmorl node. MRI was performed at baseline and at the last follow-up evaluation to observe changes in disc degeneration (disc height and nucleus pulposus signal) and Modic changes.

RESULTS: The reduction rate in the central area was significantly lower than that in the peripheral area (P = 0.017). In patients with successful reduction, 90.9% (20/22) of the endplates healed with increased curvature. In patients with an unsuccessful endplate reduction, 63.4% (26/41) of the endplates healed irregularly, and 34.1% (14/41) of the endplates formed traumatic Schmorl nodes. Endplate reduction was closely related to the final healing morphology of the endplate (P < 0.001), which had a significant protective effect on the degeneration of the intervertebral disc. At the last follow-up evaluation, there was no statistically significant correlation between different endplate healing morphologies and new Modic changes.

CONCLUSIONS: The reduction rate in the central area is significantly lower than that in the peripheral area. Although all of the intervertebral discs corresponding to fractured endplates had degenerated to different degrees, successful endplate fracture reduction can obviously delay the degeneration of intervertebral discs.

PMID:35435517 | DOI:10.1007/s00586-022-07215-w

Parasitol Res. 2022 Apr 18. doi: 10.1007/s00436-022-07522-7. Online ahead of print.

ABSTRACT

Parasitism is a dynamic ecological phenomenon that is constantly influenced by the environment and intrinsic factors of the host. We aimed to evaluate the influence of vegetation, environmental temperature, reproductive conditions, sex, and body condition (BC) on the detection of Trypanosoma spp. in the blood of Thrichomys fosteri in the Pantanal region, an enzootic area for trypanosomiasis. Whole blood was collected from the tip of the tail, and nPCR was performed for Trypanosoma spp. detection from the DNA extracted from the resultant blood clot. Statistical analyses were performed using generalized linear models. Our results showed that there is a greater probability of detection of Trypanosoma spp. in the bloodstream of animals with the highest BC values in periods with mild temperatures. Since T. fosteri is an abundant and common prey for carnivores, even in periods with low temperatures and consequent decrease in the reproduction and activities of the blood-sucking arthropod vectors, the maintenance of Trypanosoma spp. in the studied area would be guaranteed via predation (trophic network) of T. fosteri individuals with good BC and patent parasitemia. Furthermore, T. fosteri, which displays Trypanosoma spp. in the bloodstream, would be reproducing adequately because we found no influence between the reproductive condition and the detection of Trypanosoma spp. in T. fosteri. The caviomorph rodent T. fostei is an important species for the maintenance of Trypanosoma spp. in the Pantanal biome.

PMID:35435514 | DOI:10.1007/s00436-022-07522-7

Clin Oral Investig. 2022 Apr 18. doi: 10.1007/s00784-022-04412-1. Online ahead of print.

ABSTRACT

OBJECTIVE: The aim of this study was to evaluate the effect of four different finishing procedures on the fatigue strength of a fully stabilized zirconia (5Y-FSZ) material.

MATERIALS AND METHODS: Disc-shaped specimens of a 5Y-FSZ (Katana UTML, Kuraray Noritake) were made (ISO 6872-2015), grinded with 600- and 1200-grit silicon carbide paper, sintered as recommended, and randomly assigned into four groups according to the finishing technique: C (control, as-sintered), P (polished with polishing rubbers), G (glaze application – powder/liquid technique), and PG (polished with polishing rubbers + glaze application – powder/liquid). Then fatigue strength (staircase method), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses were performed.

RESULTS: The C group presented the lowest fatigue strength, while the PG group presented the highest. The P and G groups presented intermediate behavior, presenting similar statistical results. XRD showed similar crystalline phase patterns for all groups. SEM images revealed some changes in the zirconia surface, with the P group presenting some scratches on the surface, while the scratches in the PG group were filled with the glaze material.

CONCLUSION: None of the techniques analyzed in this study impaired the fatigue strength of fully stabilized zirconia. Importantly, the polishing rubbers combined with glaze application (PG group) improved its fatigue strength.

CLINICAL RELEVANCE: The polishing rubbers followed by glaze application improve the fatigue strength in ultra-translucent zirconia.

PMID:35435492 | DOI:10.1007/s00784-022-04412-1

J Cancer Res Clin Oncol. 2022 Apr 18. doi: 10.1007/s00432-022-03925-2. Online ahead of print.

ABSTRACT

OBJECTIVE: The levels of platelet-related inflammation indicators and sarcopenia have been reported to affect the survival of patients with cancer. To evaluate the prognostic influence of platelet count (PLT), platelet lymphocyte ratio (PLR), and systemic immune inflammation index (SII), and SII combined with sarcopenia on the survival of patients with gastric cancer (GC).

METHODS: A total of 1133 patients with GC (812 male and 321 female, average age: 59.43 years) were evaluated. Receiver-operating characteristic curves were used to determine the best cutoff values of PLT, PLR, and SII, and univariate and multivariate Cox risk regression models were used to evaluate whether SII is an independent predictor of overall survival (OS). The prognostic SS (SII-sarcopenia) was established based on SII and sarcopenia. Finally, a comprehensive analysis of the prognostic SS was performed.

RESULTS: SII had the strongest prognostic effect. The SII and OS of patients with GC were in an inverted U-shape (adjusted HR = 1.07; 95% CI 0.97-1.19; adjusted P = 0.179). In patients with SII > 1800, SII was negatively correlated with OS (adjusted HR = 0.57; 95% CI 0.29-1.12; adjusted P = 0.102), however, there is no statistical difference. Interestingly, a high SS was associated with a poorer prognosis. The higher the SS score was, the worse the OS (P < 0.001).

CONCLUSION: SII is an independent prognostic indicator of GC, and high SII is related to poor prognosis. A higher SS score had worse survival. Thus, the prognostic SS is a reliable predictor of OS in patients with GC.

PMID:35435489 | DOI:10.1007/s00432-022-03925-2

Knee Surg Sports Traumatol Arthrosc. 2022 Apr 18. doi: 10.1007/s00167-022-06973-w. Online ahead of print.

ABSTRACT

PURPOSE: There is a lack of consensus regarding need for Venous Thrombo Embolism (VTE) prophylaxis following arthroscopic knee surgery and open soft tissue knee reconstruction. Clear cut guidelines like ones for trauma surgery and arthroplasty do not exist and the published literature is limited to case reports with a few society guidelines. Given this lack of consensus, we conducted a modified Delphi questionnaire of international experts to provide recommendations on this topic.

METHODS: The consensus statements were generated using an anonymised 3 round modified Delphi questionnaire, sent to an international panel of 38 knee surgeons, with an 80% agreement being set as the limit for consensus. The responses were analysed using descriptive statistics with measures like mode, median and box plots. Feedback was provided to all panelists based on responses from the previous rounds to help generate the consensus.

RESULTS: Six consensus statements were generated after the three rounds of Delphi. Patient factors, prolonged surgery duration and family history of thrombogenic events emerged as the main points to be taken into consideration for prophylaxis.

CONCLUSION: It was established through this study, that there exists a select group of patients undergoing arthroscopic surgery that justify the usage of VTE prophylaxis. The expert responses to most of the questions in different scenarios favoured usage of VTE prophylaxis based on patient factors like advanced age, past history of VTE, smoking, oral contraceptive use etc. LEVEL OF EVIDENCE: Level V.

PMID:35435469 | DOI:10.1007/s00167-022-06973-w