The Epidemic Characteristics of Stroke Death from 2012 to 2021 in Chongqing, China.

INTRODUCTION: Stroke has become a major disease that threatens the global population's health and is a major public health problem that needs to be solved in China. Therefore, it is essential to analyze the trend of the mortality of stroke and its epidemic characteristic of stroke death. METHODS: Death cases of stroke were reported to the national death registry system by the medical staff of all medical institutions, and the population data every year were obtained from District or County's Statistic Bureau in Chongqing. They were analyzed to calculate the mortality, age-standardized mortality rate by Chinese standardization population (ASMRC), age-specific mortality, proportion, and annual percent of change (APC) according to the ICD-10 code. ASMRC was based on the standard population of the 6th census in China, 2010. The stroke mortality of each subgroup was compared using the χ2 test. Trend analysis was presented by APC. RESULTS: The crude mortality of stroke increased from 96.29 per 100,000 in 2012 to 115.93 per 100,000 significantly, with the APC of 2.02% (t = 2.82, p = 0.022) in Chongqing. ASMRC of stroke was 56.47 per 100,000 in 2012 and 54.70 per 100,000 in 2021, and its trend change was stable (APC = -0.01, t = 0.07, p = 0.947). The crude mortality of stroke in males was higher than that in females every year (p < 0.05). The death proportion of intracerebral hemorrhage dwindled from 60.53% in 2012 to 49.88% in 2021, whereas the death proportion of ischemic stroke increased from 20.92% in 2012 to 39.96% in 2021. The average age of stroke death was delayed from 73.43 years old in 2012 to 76.52 years old in 2021 significantly (t = 18.12, p < 0.001). The percentage of stroke death at home increased from 75.23% in 2012 to 79.23% in 2021, while the percentage of stroke death at hospitals decreased from 17.89% in 2012 to 15.89% in 2021. CONCLUSION: The crude mortality of stroke surged, and intracerebral hemorrhage was the main death cause of all subtypes. The mortality of stroke in males and rural residents was higher than that in females and urban residents. Most stroke deaths occurred at home. Male and rural residents were crucial populations for stroke prevention and control. There should be improved medical resources in rural areas and enhanced capability of stroke diagnosis and treatment.

Shifts in Clinical Characteristics, Treatment, and Outcome for Rheumatic Mitral Stenosis: Insights From a 20-Year Multicentre Registry Study in Korea.

BACKGROUND: The rapid economic development of South Korea provides a unique model to study changes in the clinical characteristics, treatment approaches, and clinical outcomes of patients with rheumatic mitral stenosis (MS) relative to socioeconomic growth. METHODS: From the Multicenter mitrAl STEnosis with Rheumatic etiology (MASTER) registry, 2,337 patients diagnosed with moderate or severe rheumatic MS between January 2001 and December 2020 were analyzed. Patients were grouped into consecutive 5-year intervals based on their year of diagnosis. Clinical characteristics, echocardiographic data, and clinical outcomes were assessed. RESULTS: Over 20 years, the severity of mitral stenosis increased from 79.1% to 90.2%; similarly, the average age at diagnosis increased from 54.3 to 63.0 years (all P < 0.001). Comorbidities such as hypertension and atrial fibrillation increased (6.3% to 29.5% and 41.4% to 46.9%, respectively; all P for trend < 0.05). The rate of mitral intervention within five years after diagnosis increased from 31.2% to 47.4% (P for trend < 0.001). However, clinical outcomes of rheumatic mitral stenosis deteriorated over time in the composite outcomes (log-rank test, P < 0.001). Conversely, the incidence of stroke remained stable (60.6-73.7%; P < 0.001), which might be attributed to the increased use of anticoagulation therapy. CONCLUSION: This study observed an increase in patient age, comorbidities, and valve disease severity as the country transitioned from a developing to developed status. Despite a rise in mitral valve interventions, clinical outcomes deteriorated over 20 years, highlighting the need for modified treatment approaches to improve patient outcomes.

Trend change analysis of postural balance in Parkinson's disease discriminates between medication state.

BACKGROUND: Maintaining static balance is relevant and common in everyday life and it depends on a correct intersegmental coordination. A change or reduction in postural capacity has been linked to increased risk of falls. People with Parkinson's disease (pwPD) experience motor symptoms affecting the maintenance of a stable posture. The aim of the study is to understand the intersegmental changes in postural sway and to apply a trend change analysis to uncover different movement strategies between pwPD and healthy adults. METHODS: In total, 61 healthy participants, 40 young (YO), 21 old participants (OP), and 29 pwPD (13 during medication off, PDoff; 23 during medication on, PDon) were included. Participants stood quietly for 10 s as part of the Short Physical Performance Battery. Inertial measurement units (IMU) at the head, sternum, and lumbar region were used to extract postural parameters and a trend change analysis (TCA) was performed to compare between groups. OBJECTIVE: This study aims to explore the potential application of TCA for the assessment of postural stability using IMUs, and secondly, to employ this analysis within the context of neurological diseases, specifically Parkinson's disease. RESULTS: Comparison of sensors locations revealed significant differences between head, sternum and pelvis for almost all parameters and cohorts. When comparing PDon and PDoff, the TCA revealed differences that were not seen by any other parameter. CONCLUSIONS: While all parameters could differentiate between sensor locations, no group differences could be uncovered except for the TCA that allowed to distinguish between the PD on/off. The potential of the TCA to assess disease progression, response to treatment or even the prodromal PD phase should be explored in future studies. TRIAL REGISTRATION: The research procedure was approved by the ethical committee of the Medical Faculty of Kiel University (D438/18). The study is registered in the German Clinical Trials Register (DRKS00022998).

Satellite observed reversal in trends of spring phenology in the middle-high latitudes of the Northern Hemisphere during the global warming hiatus.

The start of the growing season (SOS) is essential to track the responses of vegetation to climate change. However, recent findings on whether the SOS in the middle-high latitudes of the Northern Hemisphere (NH) continued to advance or reversed during the global warming hiatus were not consistent. It is necessary to investigate the causes of this controversy and to examine the relationship between the SOS and preseason temperature trends. To this end, we first applied four widely used phenology extraction methods to derive the SOS from the GIMMS NDVI3g dataset and then used the ensemble empirical modal decomposition (EEMD) method to extract the nonlinear trends of the SOS and preseason temperature. Our results clarify, for the first time, that the limitations of the linear assumption-based trend analysis methods are an important but overlooked cause of the discrepancies among existing studies on whether the SOS was advanced or delayed in the NH (>30° N) during the global warming hiatus. We further revealed the range of the mismatches between the SOS and preseason temperature trends at the latitude, altitude and biome levels. Specifically, we discovered that the SOS in the NH (>30° N) obtained by the four phenology extraction methods showed a significant reversal from advance to delay during the global warming hiatus, and the corresponding average rate of change was very small. The area showing increasing preseason temperatures decreased during the global warming hiatus, but it always occupied most of the NH (>30° N). However, delayed SOS trends were dominant in the NH from 50° N to 60° N, above 3000 m and in biomes other than TBMF and BF. Accordingly, using an EEMD-like approach to evaluate the changes in the SOS and preseason temperature is necessary for improving our understanding of the changes in the SOS and their association with climate.

Balance assessment in selected stages of Parkinson's disease using trend change analysis.

BACKGROUND: Balance disorders in patients diagnosed with Parkinson's disease (PD) are associated with a change in balance-keeping strategy and reflex disorders which regulate the maintenance of vertical body posture. Center of foot pressure (COP) displacement signals were analyzed during quiet standing experiments to define such changes. The research aimed to apply stock exchange indices based on the trend change analyses to the assessment of a level of the Parkinson disease progression on the grounds of the analysis of the COP signals. METHODS: 30 patients in two stages of PD, 40 elderly participants, and 20 individuals at a young age were studied. Each person was subjected to 3 measurements with open and closed eyes. A technical analysis of the COP displacement signal was performed, and the following quantities were determined: indices related to the number of trend changes (TCI), indices defining a mean time (TCI_dT), and mean displacement (TCI_dS) and mean velocity (TCI_dV) between such changes. RESULTS: The results indicate a higher TCI value for PD than for aged-matched control group (p < 0.05). In the case of PD patients, there was also an increase in the TCI_dS value by 2-5 mm, which mainly contributed to the increase in TCI_dV. Statistically significant differences for the TCI_dT values occurred between all groups in which differences in the average COP velocity were noted. CONCLUSIONS: The TCI and TCI_dV results obtained for the healthy participants enabled the development of indices supporting PD diagnostics. The causes of the TCI_dV changes in patients were determined, i.e., whether they resulted from an increase in the TCI_dT or TCI_dS between the moments of trend changes indicated by the developed algorithm. The developed methodology provides new information on the impact of PD on the strategy of maintaining balance, which was impossible to obtain using currently used analyses. Trial registration The conducted research is an observational study and does not include a health care intervention. Participants gave their consent to participate in the research and the procedure was approved by the Institutional Bioethics Committee.

Epidemiological and clinical characteristics of hospitalized unintentional injuries among children in central China from 2017-2023.

Objectives: To examine the epidemiological and clinical characteristics of hospitalized unintentional injuries among children in Central China and theoretically propose preventive and control measures. Methods: We conducted a retrospective study of children aged 0-18 years with unintentional injuries who were admitted to a tertiary hospital in Central China from January 2017 to December 2023. We examined various aspects of the unintentional injuries, including age, gender, urban-rural distribution, external causes, trends, location of injury, cost, and length of stay. Results: A total of 20,166 children with hospitalized unintentional injuries were enrolled. The median age with IQR was 2.8 (1.6, 5.1) years, with majority of the patients (57.0%) were aged 1-3 years, while the fewest were aged 11-18 years. The male-to-female ratio was 1.8:1, and the urban-to-rural ratio was 1.1:1. The most common external causes were foreign bodies (41.7%), exposure to inanimate mechanical forces (25.1%), and falls (22.1%). The most frequently injured body parts were head (72.5%). The total number of unintentional injuries exhibited an increasing trend from 2017-2022, and a decreasing trend from 2022-2023. The urban-rural distribution reversed after 2020. The overall hospitalization cost was 20,810,870.4 USD, with an median cost of 758.7 (556.4, 1,186.2) USD per person. Conclusion: Unintentional injuries imposed a heavy burden on society and families. However, the number of cases and the urban-rural distribution showed significant trend changes from 2017-2023. The external causes varied by age group, gender, and region, while prevention and control measures should be developed accordingly.

Analysis of changes in nutrient salts and other water quality indexes in the pond water for largemouth bass (micropterus salmoides) farming.

To explore the changes in nitrite nitrogen, ammoniacal nitrogen, nitrate nitrogen, phosphates, pH, dissolved oxygen, salinity, and water temperature over time and the correlations and mutual influences between these indexes in the traditional farming of largemouth bass, this study selected three ponds in Lizigu Farm in Baodi District of Tianjin, China as research objects. From May to October 2021, nutrient salts and other water quality indexes in the ponds were measured, and water samples were collected at different depths for repetition, Water is collected from the ponds using Plexiglas samplers and sent back to the lab for determination of water quality indexes using our national laboratory standards. According to the analysis of the measurement results, in traditional farming, nitrite nitrogen, ammoniacal nitrogen, nitrate nitrogen, phosphates, pH, dissolved oxygen, salinity, and water temperature in the ponds for largemouth bass all change significantly over time, with different changing trends and certain correlations with each other. In particular, nutrient salts indexes in ponds are influenced by other water quality indexes, human activities, and phytoplankton. During the breeding process, strengthening the dynamic monitoring of nutrient salts and other water quality indexes in the ponds and adjusting the nitrogen, phosphorus, and ammonia levels in the ponds artificially play an important role in preventing eutrophication in the water and promoting the green and sustainable production of pond ecosystems, in particular, allowing better quality growth of the largemouth bass, as well as ensuring the production and economic efficiency. This study provides a theoretical basis and data support for further optimization of traditional pond aquaculture in similar regions, in order to provide aquatic products with better quality and achieve higher economic benefits.

[Xiaojiang River Basin Ecological Environmental Quality Spatiotemporal Pattern and Evolutionary Trend Analysis Using GEE from 1990 to 2022].

Assessment and monitoring of the quality of the ecological environment in the area is a very important fundamental task in the development of ecological civilization in the Xiaojiang River Basin in Yunnan Province, which serves as a demonstration area for ecological restoration in the upper reaches of the Yangtze River. The Landsat remote sensing images from 1990, 1995, 2000, 2005, 2010, 2014, 2018, and 2022 were chosen, and the four indexes of greenness （NDMVI）, humidity （WET）, dryness （NDBSI）, and heat （LST） were extracted. The remote sensing ecological index （RSEI） was created using the principal component analysis method, then the spatial and temporal patterns and trends of ecological quality in the Xiaojiang River Basin between 1990 and 2022 were examined using the GEE platform, ArcGIS 10.7 platform, and Python platform, combining the analysis methods of geographic information mapping, coefficient of variation, Mann-Kendall trend test, Sen's slope estimation, and Hurst's index. The findings demonstrated that： ① the ecological quality of the study area had more obvious geographic differentiation spatially, and by 2022, the areas with excellent and good ecological quality grades were primarily distributed in the areas with better alpine vegetation cover, and those with poor ecological quality were primarily distributed in the areas of the mudslide ravines with relatively low terrain. On a time scale, the study area's RSEI index increased from 0.41 in 1990 to 0.55 in 2022, with a fluctuating overall trend of ecological quality improvement and an average increase of 0.048（10 a） -1； this progress was directly related to a number of ecological construction initiatives that have been energetically carried out, such as converting farms to forests, preventing mudslides, saving soil and water, managing heavy metal contamination, etc. ② The RSEI was more appropriate for the evaluation of ecological quality in alpine ravine areas because, in comparison to the NDVI index, the NDVMI adopted in this study was more sensitive to vegetation information in topographic undulation areas, especially in shaded areas, and could more accurately and quantitatively describe the vegetation information. ③ The RSEI in the Xiaojiang River Basin had a mean coefficient of variation of 0.202. Overall, its volatility was low, and its high volatility was mostly concentrated in the mudslide gully area along both sides of the Xiaojiang River fracture zone, where the surface was made up of bare rocks and sediment that was easily impacted by the changing of the seasons, the climate, and human activity. ④ The quality of the ecological environment in the region was significantly improving, with the rising area reaching 85.72% of the total area and the declining area accounting for approximately 10.15% of the total area. The future trend of change will be dominated by ongoing improvement and future degradation, accounting for 44.75% and 39.97%, respectively. It is important to pay close attention to areas that could potentially degrade. The findings of this study can serve as a theoretical foundation for additional ecological environmental conservation, management, and sustainable development in the Xiaojiang River Basin.

[Nonlinear Variations in PM2. 5 Concentration in the Three Major Urban Agglomerations in China].

ITA and Beast methods were used to quantitatively analyze the nonlinear process of a PM2.5 concentration time series based on the PM2.5 concentration data of the three major urban agglomerations in China. The results showed that： ① the degree of the PM2.5 pollution in the three major urban agglomerations had decreased， and the high-concentration areas had noticeably shrunk. The degree of spatial polarization of PM2.5 concentration was reduced， and the spatial difference was narrowed. The PM2.5 concentration in most areas showed downward trends， but the degree of change was not the same. Compared with the YRD and PRD， the concentration of PM2.5 in the BTH was still at a relatively high level. ② The concentration of PM2.5 in the three major urban agglomerations had seasonal variation characteristics that were high in winter and spring and low in summer and autumn. There were obvious differences in PM2.5 concentration between winter and summer， and the convergence of PM2.5 concentration in summer was greater than that in winter. Areas with high PM2.5 concentration also had obvious downward trends， but the downward trends of PM2.5 concentration in the PRD were not obvious compared with those in the YRD and BTH. ③ The PM2.5 concentration time series of the three major urban agglomerations all had significant downward trends： Beijing-Tianjin-Hebei （BTH） > the Yangtze River Delta （YRD） > the Pearl River Delta （PRD）. The PM2.5 concentration had the largest downward trends in winter. The higher the PM2.5 pollution level， the greater the downward trends. ④ The trend component of the PM2.5 concentration time series in the BTH had two change points， and there was one change point in the seasonal component. The trend and seasonal components of the PM2.5 concentration time series in the YRD had no change point. There was no change point in the seasonal component but one change point in the trend component of the PM2.5 concentration time series in the PRD. These results can provide scientific references for regional air pollution control.

The impact of the COVID-19 pandemic on the number of brain tumor surgeries in Poland: A national database study.

BACKGROUND: The coronavirus disease (COVID-19) pandemic has greatly affected the treatment of most medical conditions. In particular, the treatment of seriously ill patients had to be adjusted due to the limited availability of in-hospital procedures. OBJECTIVES: The aim of this study was to evaluate the effects of COVID-19-related changes on neuro-oncological surgeries in the Polish medical system. MATERIAL AND METHODS: Data from the period of 2010-2020 were collected from National Health Insurance database for 2 diagnosis-related groups: A11 (complex intracranial procedures) and A12 (large intracranial procedures). The total number of procedures and diagnoses per year, trend changes and changes in procedures grouped by medical type were analyzed, including resections/biopsies, malignant/stable (nonmalignant) lesions, elective/acute procedures, and length of stay. RESULTS: Mean yearly numbers of 7177 (standard deviation (SD) = 760) procedures and 5934 (SD = 1185) diagnoses were recorded. Both numbers were growing up to 9.1% per year until 2018. From 2018, a 3.1% decrease in the number of procedures was observed, with a significantly larger decrease of 10.5% observed in 2020 (p < 0.001). The number of diagnoses decreased in 2019 by 2.7%, and by 9.2% in 2020 (p = 0.706), with a statistically significant change in the annual growth rate (p = 0.044). The number of resections decreased by 11.5% in 2020 (p = 0.204), with a significant change in the annual growth rate (p < 0.001). The number of biopsies decreased by 2.5% in 2020 (p = 0.018), with the annual decrement in 2019/2020 also being significant (p = 0.004). Decreases were observed in 2019 and 2020 for the number of malignant (0.5% and 6.3%, respectively) and nonmalignant (5.4% and 12.9%, respectively) tumors (p = 0.233 and p = 0.682 for absolute values, and p = 0.008 and p = 0.004 for the annual growth rates, respectively). The number of acute procedures in 2020 further decreased by 9.8% from 5.5% decrease in 2019 (p = 0.004), and the number of elective procedures decreased by 11.8% (p = 0.009). The annual growth rates for both acute and elective procedures were statistically significant (p < 0.001 and p < 0.001). CONCLUSIONS: The decrease in the number of neuro-oncological surgeries appeared to be much lower than the 20% decrease observed for general oncological surgeries in Poland during the COVID-19 pandemic. This seems to have resulted from postponing the treatment of less critical cases (i.e., nonmalignant and elective) and focusing on the treatment of the most precarious patients.

Spatial and Temporal Variation of Land Surface Temperature and Its Spatially Heterogeneous Response in the Urban Agglomeration on the Northern Slopes of the Tianshan Mountains, Northwest China.

An in-depth study of the influence mechanism of oasis land surface temperature (LST) in arid regions is essential to promote the stable development of the ecological environment in dry areas. Based on MODIS, MYD11A2 long time series data from 2003 to 2020, the Mann-Kendall nonparametric test, the Sen slope, combined with the Hurst index, were used to analyze and predict the trend of LST changes in the urban agglomeration on the northern slopes of the Tianshan Mountains. This paper selected nine influencing factors of the slope, aspect, air temperature, normalized vegetation index (NDVI), precipitation (P), nighttime light index (NTL), patch density (PD), mean patch area (AREA_MN), and aggregation index (AI) to analyze the spatial heterogeneity of LST from global and local perspectives using the geodetector (GD) model and multi-scale geo-weighted regression (MGWR) model. The results showed that the average LSTs of the urban agglomeration on the northern slopes of the Tianshan Mountains in spring, summer, autumn, and winter were 31.53 °C, 47.29 °C, 22.38 °C, and -5.20 °C in the four seasons from 2003 to 2020, respectively. Except for autumn, the LST of all seasons showed an increasing trend, bare soil and grass land had a warming effect, and agricultural land had a cooling effect. The results of factor detection showed that air temperature, P, and NDVI were the dominant factors affecting the spatial variation of LST. The interaction detection results showed that the interaction between air temperature and NDVI was the most significant, and the two-factor interaction was more effective than the single-factor effect on LST. The MGWR model results showed that the effects of PD on LST were positively correlated, and the impact of AREA_MN and AI on LST were negatively correlated, indicating that the dense landscape of patches has a cooling effect on LST. Overall, this study provides information for managers to carry out more targeted ecological stability regulations in arid zone oases and facilitates the development of regulatory measures to maintain the cold island effect and improve the environment.

Changing Trends in Melanoma Incidence and Decreasing Melanoma Mortality in Hungary Between 2011 and 2019: A Nationwide Epidemiological Study.

BACKGROUND: The incidence of malignant melanoma has continually increased during the past few decades, however, certain reports suggest a recent change in trends. The aim of our study was to examine the epidemiology of melanoma in Hungary. METHODS: This nationwide, retrospective, longitudinal study included melanoma patients diagnosed between 1 January 2009 and 31 December 2019 using the databases of the National Health Insurance Fund (NHIF) and Central Statistical Office (CSO) of Hungary. Age-standardized incidence and cause-specific mortality rates were calculated. RESULTS: We identified 2,426 and 2,414 new melanoma cases in 2011 and in 2019. Age-standardized incidence rates were higher in males and varied between 28.28 and 34.57/100,000 person-years (PYs), and between 22.63 and 26.72/100,000 PYs in females. We found 16.14 and 18.82% increases in male and female incidence rates from 2011 to 2015 (p=0.067 and p<0.001, respectively), and 12.77 and 11.35% decreases from 2015 to 2019 (p=0.062 and p=0.004, respectively). The change of incidence trends (2011-2015 vs. 2015-2019) was significant in females (p=0.002) and in the total melanoma population (p=0.011), but not in the male population (p=0.063). A 16.55% (95% CI: -27.07 to -4.59; p=0.013) decrease in mortality rates was found in the overall melanoma population. CONCLUSIONS: We observed a significant trend change in melanoma incidence in the female and total melanoma population, and a significant decrease in mortality in the total melanoma population. These changes may be attributed to intensive melanoma awareness campaigns as well as to the increase in screening and access to modern therapies.

[Analysis of trends on smoking prevalence and its risk factors in Shaanxi province 2007-2015].

Objective: To analyze the trend of smoking prevalence and its risk factors among adults in Shaanxi province from 2007 to 2015. Methods: We used data from China Chronic Disease and Risk Factor Surveillance in 2007, 2010, 2013 and 2015. The current smoking prevalence and trends of the four surveys were calculated. Its risk factors were analyzed by multivariate logistic regression from each survey and then from all pooled data of the three surveys. Results: The number of participants in 2007, 2010, 2013 and 2015 was 1 542, 3 000, 10 166 and 6 330, respectively. The current smoking prevalence dropped from 34.34% in 2007 to 26.22% in 2013, but increased to 28.33% in 2015 (trend χ(2) test: Z=2.53, P=0.01). The results from four pooled data showed that the current smoking prevalence of men was higher than that of women (OR=75.03, 95%CI: 63.57-88.55). The current smoking prevalence of people aged 45-59 was higher than that of people aged 18-44 (OR=1.28, 95%CI: 1.15-1.41). In addition, the current smoking prevalence of those who were educated for 7-9 years and more than 9 years were higher than those who were educated for less than 6 years (people with education for 7-9 years OR=1.44, 95%CI: 1.29-1.61; people with education >9 years OR=1.43, 95%CI: 1.26-1.63). The current smoking prevalence of the single was lower than those of married/cohabitants (OR=0.54, 95%CI: 0.37-0.77). The current smoking prevalence of retirees were lower than those of employees (OR=0.46, 95%CI: 0.38-0.57) and smoking prevalence of alcohol drinkers were higher than those of non-drinkers (OR=2.92, 95%CI: 2.67-3.19). Conclusion: From 2007 to 2015, the current smoking prevalence of Shaanxi population was high and the trends remained stable. It is necessary to strengthen smoking control and health education for men, people over 45 years old, people with education level 7 years and above, and working personnel in Shaanxi province.

Assessing Trends in Functional and Structural Characteristics: A Survey of Statistical Methods With an Example From Ophthalmology.

PURPOSE: Clinical decisions on treatment are usually based on short-term records of consecutive measurements of structure and function. Useful models for analyzing average trends and a description of statistical methods for classifying individual subjects on the basis of subject-specific trend progressions are presented. METHODS: Random effects trend models allow intercepts and slopes of the trend regression to vary across subjects around group-specific mean intercepts and mean slopes. Model results assess whether average intercepts and slopes and subject variability in intercepts and slopes are the same across groups. Fisher's discriminant functions are used for classification. RESULTS: Methods are presented and illustrated on structural visual data from a multiyear perimetry study. Average thickness of the ganglion cell layer from the optical coherence tomography macula scan and of the retinal nerve fiber layer from the optic disc scan for both glaucoma patients on optimal treatment and normal subjects are analyzed. The random effects trend model shows that average intercepts of glaucoma patients and normal subjects are quite different, but that average slopes are the same, and that the subject variability in both intercepts and slopes is larger for the glaucoma group. These findings explain why the subject-specific trend progression is not a good classifier; it is the level of the measurement (intercept or baseline value) that carries useful information in this particular cohort example. TRANSLATIONAL RELEVANCE: Clinicians base decisions on short-term records of consecutive measurements and need simple statistical tools to analyze the information. This paper discusses useful methods for analyzing short time series data. Model results assess whether there exist significant trends and whether average trends are different across groups. The paper discusses whether clinical measures classify patients reliably into disease groups, given their variability. With ever more available data, classification plays a central role of personalized medicine.

Does Testing More Frequently Shorten the Time to Detect Disease Progression?

PURPOSE: With the rise of smartphone devices to monitor health status remotely, it is tempting to conclude that sampling more often will provide a more sensitive means of detecting changes in health status earlier over time, when interventions may improve outcomes. METHODS: The answer to this question is derived in the context of a model where observations are generated from a linear-trend model with independent as well as autocorrelated autoregressive-moving average, or ARMA(1,1), errors. RESULTS: The results imply a cautionary message that an increase in the sampling frequency may not always lead to a faster detection of trend changes. The benefit of rapid successive observations depends on how observations, taken closely together in time, are correlated. CONCLUSIONS: Shortening the observation period by half can be accomplished by increasing the number of independent observations to maintain the same power for detecting change over time. However, a strategy to detect progression of disease sooner by taking numerous closely spaced measurements over a shortened interval is limited by the degree of autocorrelation among adjacent observations. We provide a statistical model of disease progression that allows for autocorrelation among successive measurements, and obtain the power of detecting a linear change of specified magnitude when equal-spaced observations are taken over a given time interval. TRANSLATIONAL RELEVANCE: New emerging technology for home monitoring of visual function will provide a means to monitor sensory status more frequently. The model proposed here takes into account how successive measurements are correlated, which impacts the number of measurements needed to detect a significant change in status.