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3. Missing-Data Handling Methods for Lifelogs-Based Wellness Index Estimation: Comparative Analysis With Panel Data

Author

Kim, Ki-Hun and Kim, Kwang-Jae

Subjects
Computer applications to medicine. Medical informatics, R858-859.7
Abstract

BackgroundA lifelogs-based wellness index (LWI) is a function for calculating wellness scores based on health behavior lifelogs (eg, daily walking steps and sleep times collected via a smartwatch). A wellness score intuitively shows the users of smart wellness services the overall condition of their health behaviors. LWI development includes estimation (ie, estimating coefficients in LWI with data). A panel data set comprising health behavior lifelogs allows LWI estimation to control for unobserved variables, thereby resulting in less bias. However, these data sets typically have missing data due to events that occur in daily life (eg, smart devices stop collecting data when batteries are depleted), which can introduce biases into LWI coefficients. Thus, the appropriate choice of method to handle missing data is important for reducing biases in LWI estimations with panel data. However, there is a lack of research in this area. ObjectiveThis study aims to identify a suitable missing-data handling method for LWI estimation with panel data. MethodsListwise deletion, mean imputation, expectation maximization–based multiple imputation, predictive-mean matching–based multiple imputation, k-nearest neighbors–based imputation, and low-rank approximation–based imputation were comparatively evaluated by simulating an existing case of LWI development. A panel data set comprising health behavior lifelogs of 41 college students over 4 weeks was transformed into a reference data set without any missing data. Then, 200 simulated data sets were generated by randomly introducing missing data at proportions from 1% to 80%. The missing-data handling methods were each applied to transform the simulated data sets into complete data sets, and coefficients in a linear LWI were estimated for each complete data set. For each proportion for each method, a bias measure was calculated by comparing the estimated coefficient values with values estimated from the reference data set. ResultsMethods performed differently depending on the proportion of missing data. For 1% to 30% proportions, low-rank approximation–based imputation, predictive-mean matching–based multiple imputation, and expectation maximization–based multiple imputation were superior. For 31% to 60% proportions, low-rank approximation–based imputation and predictive-mean matching–based multiple imputation performed best. For over 60% proportions, only low-rank approximation–based imputation performed acceptably. ConclusionsLow-rank approximation–based imputation was the best of the 6 data-handling methods regardless of the proportion of missing data. This superiority is generalizable to other panel data sets comprising health behavior lifelogs given their verified low-rank nature, for which low-rank approximation–based imputation is known to perform effectively. This result will guide missing-data handling in reducing coefficient biases in new development cases of linear LWIs with panel data.

Published
2020
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9. Circulating tumor DNA status and dynamics predict recurrence in patients with resected extrahepatic cholangiocarcinoma

Author

Yoo, Changhoon, Jeong, Hyehyun, Jeong, Jae Ho, Kim, Kyu-pyo, Lee, Seonmin, Ryoo, Baek-Yeol, Hwang, Dae Wook, Lee, Jae Hoon, Moon, Deog-Bog, Kim, Ki-Hun, Lee, Sang Soo, Song, Tae Jun, Oh, Dongwook, Lee, Myung Ah, Chon, Hong Jae, Lee, Ji Sung, Laliotis, George, Rivero-Hinojosa, Samuel, Spickard, Erik, Renner, Derrick, Dutta, Punashi, Palsuledesai, Charuta C., Sharma, Shruti, Malhotra, Meenakshi, Jurdi, Adham, and Liu, Minetta C.

Published
2024
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23. Edoxaban-based long-term antithrombotic therapy in patients with atrial fibrillation and stable coronary disease: Rationale and design of the randomized EPIC-CAD trial

Author

Cho, Min Soo, Kang, Do-Yoon, Oh, Yong-Seog, Lee, Chang Hoon, Choi, Eue-Keun, Lee, Ji Hyun, Kwon, Chang Hee, Park, Gyung-Min, Park, Hyun Woo, Park, Kyoung-Ha, Park, Kyoung-Min, Hwang, Jongmin, Yoo, Ki-Dong, Cho, Young-Rak, Kim, Yoo Ri, Hwang, Ki Won, Jin, Eun Sun, Kim, Pum-Joon, Kim, Ki Hun, Park, Duk-Woo, and Nam, Gi-Byoung

Published
2022
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26. Association between body mass index and results of cryoballoon ablation in Korean patients with atrial fibrillation: an analysis from Korean Heart Rhythm Society Cryoablation registry

Author

Ahn, Hyun Jin, primary, Oh, Il-Young, additional, Choi, JeongMin, additional, Lee, Kyung-Yeon, additional, Ahn, Hyo-Jeong, additional, Kwon, Soonil, additional, Choi, Eue-Keun, additional, Oh, Seil, additional, Kim, Ju Youn, additional, Cha, Myung-Jin, additional, Kwon, Chang Hee, additional, Lee, Sung Ho, additional, Park, Junbeom, additional, Kim, Ki-Hun, additional, Yang, Pil-Sung, additional, Kim, Jun-Hyung, additional, Shim, Jaemin, additional, Lim, Hong Euy, additional, and Lee, So-Ryoung, additional

Published
2024
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39. Over 500 Liver Transplants Including More Than 400 Living-Donor Liver Transplants in 2019 at Asan Medical Center

Author

Moon, Deok-Bog, Lee, Sung-Gyu, Chung, Yong-Kyu, Kang, Woo-Hyoung, Kim, Ki-Hun, Song, Gi-Won, Jung, Dong-Hwan, Ha, Tae-Yong, Ahn, Chul-Soo, Park, Gil-Chun, Hwang, Shin, Yoon, Young-In, Cho, Hwui-Dong, Kang, Sang-Hyun, Choi, Jin-Uk, Jeong, I-Jy, Na, Byeong-Gon, Kim, Min-Jae, Kim, Sang-Hoon, Sung, Kyu-Bo, Ko, Gi-Young, Kwon, Dong-Il, Lee, Sung-Koo, Oh, Dong-Wook, Hwang, Gyu-Sam, Song, Jun-Gol, Jun, In-Gu, Moon, Young-Jin, Lee, Sang-Oh, Kim, Sung-Han, and Huh, Jin-Won

Published
2021
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41. Long‐term clinical impact of early recurrence of atrial tachyarrhythmia after cryoballoon ablation in patients with atrial fibrillation.

Author

Park, Jinsun, Cha, Myung‐Jin, Kwon, Chang Hee, Cho, Min Soo, Nam, Gi‐Byoung, Oh, Il‐Young, Lee, So‐Ryoung, Kim, Ju Youn, Lee, Sung Ho, Park, Junbeom, Kim, Ki‐Hun, Yang, Pil‐Sung, Kim, Jun Hyung, Shim, Jaemin, and Lim, Hong Euy

Subjects
RISK assessment, HEART atrium, RESEARCH funding, CRYOSURGERY, TREATMENT effectiveness, REPORTING of diseases, DESCRIPTIVE statistics, MULTIVARIATE analysis, ATRIAL fibrillation, DISEASE relapse, TACHYCARDIA, CONFIDENCE intervals, TIME, PATIENT aftercare, DISEASE risk factors
Abstract

Introduction: The impact of early recurrence of atrial tachyarrhythmia (ERAT) within the 90‐day blanking period on long‐term outcomes in atrial fibrillation (AF) patients undergoing cryoballoon ablation (CBA) is controversial. This study aimed to assess the relationship between ERAT and late recurrence of atrial tachyarrhythmia (LRAT) post‐CBA. Methods: Utilizing data from a multicenter registry in Korea (May 2018 to June 2022), we analyzed the presence and timing of ERAT (<30, 30–60, and 60–90 days) and its association with LRAT risk after CBA. LRAT was defined as any recurrence of AF, atrial flutter, or atrial tachycardia lasting more than 30 s beyond the 90 days. Results: Out of 2636 patients, 745 (28.2%) experienced ERAT post‐CBA. Over an average follow‐up period of 21.2 ± 10.3 months, LRAT was observed in 874 (33.1%) patients. Patients with ERAT had significantly lower 1‐year LRAT freedom compared to those without ERAT (42.6% vs. 85.5%, p <.001). Multivariate analysis identified ERAT as a potential predictor of LRAT, with a hazard ratio (HR) of 3.98 (95% confidence interval [CI], 3.47–4.57). Significant associations were noted across all examined time frames (HR, 3.84; 95% CI, 3.32–4.45 in <30 days, HR, 5.53; 95% CI, 4.13–7.42 in 30–60 days, and HR, 4.29; 95% CI, 3.12–5.89 in 60–90 days). This finding was consistently observed across all types of AF. Conclusion: ERAT during the 90‐day blanking period strongly predicts LRAT in AF patients undergoing CBA, indicating a need to reconsider the clinical significance of this period. [ABSTRACT FROM AUTHOR]

Published
2024
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43. Astrocytes Control Sensory Acuity via Tonic Inhibition in the Thalamus

Author

Kwak, Hankyul, Koh, Wuhyun, Kim, Sangwoo, Song, Kiyeong, Shin, Jeong-Im, Lee, Jung Moo, Lee, Elliot H., Bae, Jin Young, Ha, Go Eun, Oh, Ju-Eun, Park, Yongmin Mason, Kim, Sunpil, Feng, Jiesi, Lee, Seung Eun, Choi, Ji Won, Kim, Ki Hun, Kim, Yoo Sung, Woo, Junsung, Lee, Dongsu, Son, Taehwang, Kwon, Soon Woo, Park, Ki Duk, Yoon, Bo-Eun, Lee, Jaeick, Li, Yulong, Lee, Hyunbeom, Bae, Yong Chul, Lee, C. Justin, and Cheong, Eunji

Published
2020
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50. Reconstruction of all hepatic arteries in right lobe grafts with two hepatic arteries and zero percent hepatic artery thrombosis

Author

Kim, Sung-Min, primary, Moon, Deok-Bog, additional, Ahn, Chul-Soo, additional, Park, Gil-Chun, additional, Kang, Woo-Hyung, additional, Yoon, Young-In, additional, Lee, Jung-Bok, additional, Na, Byeong-Gon, additional, Kim, Sang-Hoon, additional, Oh, Rak-kyun, additional, Hwang, Shin, additional, Ha, Tae-Yong, additional, Jung, Dong-Hwan, additional, Song, Gi-Won, additional, Kim, Ki-Hun, additional, and Lee, Sung-Gyu, additional

Published
2024
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