Research

研究業績全体についてはGoogle Scholarもご覧ください。ここでは、生物統計学の方法論を中心とした研究を紹介します。

採択・出版済み論文

[8] Hanada, K., & Kojima, M. (2026+). Integrate Meta-analysis into Specific Study (InMASS) for Estimating Target-Population Average Treatment Effect. Biometrical Journal, accepted. [arXiv]

We propose a method that uses meta-analysis to estimate the average treatment effect in a target population represented by a specific study.

[7] Hanada, K., & Sugimoto, T. (2026+). Random-effects meta-analysis via generalized linear mixed models: A Bartlett-corrected approach for few studies. Biometrics, accepted. [arXiv, GitHub]

We develop random-effects meta-analysis under generalized linear mixed models and propose a simple Bartlett correction that gives accurate interval estimation with few studies.

[6] Hanada, K., & Kojima, M. (2026). Random Effect Restricted Mean Survival Time Model. Journal of Biopharmaceutical Statistics, 1-16. [論文, DOI, arXiv]

We introduce random effects into RMST regression, enabling cluster-specific shrinkage estimates based on the overall effect.

[5] Kojima, M., Orihara, S., Hanada, K., & Ohigashi, T. (2026). Sample size re-estimation in blinded hybrid-control design using inverse probability weighting. Statistics in Medicine, 45(3-5), e70429. [論文, DOI, arXiv]

[4] Kojima, M., Mano, H., Yamada, K., Hanada, K., Tanaka, Y., & Moriya, J. (2025). Adjusting confidence intervals under covariate-adaptive randomization in non-inferiority and equivalence trials. Contemporary Clinical Trials, 158, 108099. [論文, arXiv]

We propose confidence-interval adjustments for non-inferiority and equivalence testing under rerandomization and covariate-adaptive randomization.

[3] 花田圭佑、杉本知之 (2024). イベント時間アウトカムに対する個人データ復元と要約統計量に基づくメタアナリシスとその性能. 『計量生物学』45(1), 115-131. [論文, arXiv]

生存時間データについて、個別被験者データを復元するメタアナリシスと要約統計量を用いる方法の性能をシミュレーションで比較しました。

[2] Hanada, K., Moriya, J., & Kojima, M. (2024). Comparison of baseline covariate adjustment methods for restricted mean survival time. Contemporary Clinical Trials, 138, 107440. [論文]

We compare model-based RMST analyses by simulation and identify when different adjustment methods are appropriate.

[1] Hanada, K., & Sugimoto, T. (2023). Inference using an exact distribution of test statistic for random-effects meta-analysis. Annals of the Institute of Statistical Mathematics, 75(2), 281-302. [論文, DOI]

We derive an exact distribution for a test statistic in random-effects meta-analysis and study its use for testing and interval estimation.

Medical Research（臨床研究）

[6] Tamura, T., Matsumori, T., Nishikawa, Y., Kitagawa, K., Nagai, M., Shimizu, A., Matsumoto, I., Masuda, A., Sakai, A., Yamai, T., Tomokuni, A., Ikeura, T., Ito, T., Doi, T., Miyake, H., Maruyama, H., Ishikawa-Kakiya, Y., Ogura, T., Ueno, S., Shiomi, H., Tsujimoto, A., Shintani, S., Ikeda, T., Uenoyama, Y., Emori, T., Shimatani, M., Hanada, K., Kitano, M., & Takenaka, M. (2026). Impact of Stent Type on Surgical Outcomes in Pancreatic Cancer Patients Undergoing Preoperative Biliary Drainage. Digestive Endoscopy, 38(7). [論文, DOI]

This multicentre retrospective study compared metal and plastic stents for preoperative biliary drainage in patients with pancreatic ductal adenocarcinoma receiving neoadjuvant treatment.

[5] Sagan, K., Kojima, F., Matsuzaki, I., Hanada, K., Musangile, F. Y., Nakamoto, T., Hayashi, H., Ohe, C., Ohashi, R., Nagashima, Y., Kohjimoto, Y., & Murata, S. I. (2026). Clear Cell Papillary Renal Cell Tumor Revisited: Comparison of Histologic and Immunohistochemical Profiles in Relation to VHL Allelic Status. The American Journal of Surgical Pathology.

[4] Nakayama, Y., Kume, K., Baba, T., Ayaki, T., Hanada, K., Miyamoto, K., Inoue, N., Kawakami, H., & Ito, H. (2026). Neuropathological and Molecular Features Associated With a Heterozygous DNAJC7 Mutation in Amyotrophic Lateral Sclerosis. Neuropathology and Applied Neurobiology, 52(4), e70086.

[3] Kitadani, J., Hayata, K., Goda, T., Tominaga, S., Fukuda, N., Nakai, T., Nagano, S., Hanada, K., & Kawai, M. (2026). Impact of intraoperative nerve integrity monitoring on recurrent laryngeal nerve paralysis in minimally invasive esophagectomy for esophageal cancer: a propensity score-matched analysis. Surgical Endoscopy, 1-10.

[2] Itonaga, M., Ashida, R., Tamura, T., Yamashita, Y., Kawaji, Y., Shishimoto, T., Morishita, M., Hanada, K., Kojima, F., & Kitano, M. (2026). Comparison of Nanoliposomal Irinotecan Plus Fluorouracil/Leucovorin and S-1, Irinotecan, and Oxaliplatin as Second-Line Chemotherapy After Gemcitabine Plus Nab-Paclitaxel for Unresectable Pancreatic Cancer. Journal of Hepato-Biliary-Pancreatic Sciences, 1-11.

[1] Hirano, S., Hanada, K., & Maeda, H. (2025). Potential surrogate endpoint for B-cell hematologic malignancy: A systematic review and meta-analysis. Scientific Reports, 15, 19300. [論文]

プレプリント・投稿中論文

[5] Hanada, K., & Kojima, M. (2026). Covariate-Adaptive Sample Size Re-estimation for Population-Standardized Historical Control Designs in Single-Arm Trials. arXiv preprint arXiv:2607.25159, submitted. [arXiv]

We propose covariate-adjusted sample-size planning and re-estimation for single-arm trials using population-standardized historical controls.

[4] Hanada, K., Shimokawa, T., & Maruo, K. (2026). Differentially Private One-Shot Federated Inference for Linear Mixed Models via Lossless Likelihood Reconstruction. arXiv preprint arXiv:2604.00410, submitted. [arXiv]

We propose differentially private linear mixed-model inference based only on facility-level summaries and study the privacy-accuracy tradeoff.

[3] Yamada, K., Sunami, H., Takeda, K., Hanada, K., & Kojima, M. (2026). Hybrid Non-informative and Informative Prior Model-assisted Designs for Mid-trial Dose Insertion. arXiv preprint arXiv:2602.17995, submitted. [arXiv]

[2] Kojima, M., Hanada, K., & Sato, A. (2025). A Clustering Approach for Basket Trials Based on Treatment Response Trajectories. arXiv preprint arXiv:2511.09890, submitted. [arXiv]

[1] Hanada, K., & Kojima, M. (2024). Bayesian Parametric Methods for Deriving Distribution of Restricted Mean Survival Time. arXiv preprint arXiv:2406.06071, submitted. [arXiv]

We formulate RMST under parametric survival models, add random and frailty effects, and propose Bayesian inference with consistency properties.

学会発表（国際学会）

[5] Hanada, K., Shimokawa, T., & Maruo, K. (2026). Privacy-Preserving One-Shot Federated Inference for Linear Mixed Models. 33rd International Biometric Conference, Seoul. [大会サイト]

[4] Hanada, K. (2026). Random-effects meta-analysis via generalized linear mixed models: A Bartlett-corrected approach for few studies. Recent Advances in Meta-Analysis 2026, Gottingen. [大会サイト]

[3] Hanada, K., & Sugimoto, T. (2025). Random-effects meta-analysis via generalized linear mixed models for few studies. The 13th Conference of the IASC-ARS, Ho Chi Minh City. [発表資料]

[2] Hanada, K., & Kojima, M. (2025). Integrate Meta-analysis into Specific Study for Estimating Conditional Average Treatment Effect. Joint Statistical Meetings 2025, Nashville. [ポスター]

[1] Hanada, K., & Sugimoto, T. (2019). Non-Asymptotic Properties and Behaviors for Random-Effects Meta-Analysis When the Number of Studies Is Small. The VI-th International Symposium on Biopharmaceutical Statistics, Kyoto.

学会発表（国内学会・研究会）

[15] 花田圭佑 (2026). Kaplan-Meier曲線図の統合による生存時間メタアナリシス. 日本計算機統計学会第40回大会. [大会サイト]

[14] 花田圭佑、下川敏雄、丸尾和司 (2026). 線形混合モデルに対するlossless one-shot連合学習とプライバシー保護. 2026年度日本計量生物学会年会. [大会サイト]

[13] Hanada, K. (2026). 線形混合モデルに対する差分プライベートな分散型回帰分析. 大分統計談話会第73回大会. [大会サイト]

[12] 花田圭佑、杉本知之 (2025). 少数試験に対する一般化線形ランダム効果メタアナリシスの推測. 科研費シンポジウム「データサイエンスの分野横断的基盤と実践の総合的探求」. [発表資料]

[11] 花田圭佑 (2025). 試験数が少ない場合の一般化線形ランダム効果メタアナリシス. 2025年度統計関連学会連合大会.

[10] 花田圭佑、小島将裕 (2025). 臨床試験における治療効果の推定のためのメタアナリシスの活用. 2025年度日本計量生物学会年会.

[9] 花田圭佑、杉本知之 (2024). メタアナリシスでの平均治療効果と試験間分散の同時分布とその活用. 第7回かごしまデータ科学シンポジウム.

[8] 花田圭佑、小島将裕 (2024). Random Effect Restricted Mean Survival Time Model. 2024年度統計関連学会連合大会.

[7] 花田圭佑、杉本知之 (2024). 少数試験メタアナリシスでの分散推定. 日本計算機統計学会第38回大会.

[6] 花田圭佑、杉本知之 (2023). イベント時間アウトカムの個人データ復元とメタアナリシス. 第5回かごしまデータ科学シンポジウム.

[5] 花田圭佑、守屋順之、小島将裕 (2023). 制限付き平均生存時間（RMST）の共変量調整法の比較. 2023年度統計関連学会連合大会.

[4] 花田圭佑 (2022). イベント数が少ないもとでの二値メタアナリシスの推測. 第3回かごしまデータ科学シンポジウム.

[3] 花田圭佑、杉本知之 (2019). 試験数が少ない場合のランダム効果メタアナリシスの非漸近的性質. 日本計算機統計学会第33回シンポジウム.

[2] 花田圭佑、杉本知之 (2018). ランダム効果DL層別解析における標本分布. 日本計算機統計学会第32回シンポジウム.

[1] 花田圭佑、杉本知之 (2018). 正規母集団におけるランダム効果層別解析における標本分布. 大分統計談話会第57回大会.

その他の研究成果

[1] Hanada, K. (2024). Inference and Exact Distributions for Random-Effects Meta-Analysis. Doctoral dissertation, Shiga University. [論文]

My doctoral dissertation studies meta-analysis with few studies and reconstructed individual-participant-data meta-analysis for time-to-event outcomes.

ソフトウェア

[2] Hanada, K. (2024). rmstBayespara. R package: Bayesian Restricted Mean Survival Time for Cluster Effect. [CRAN]

[1] Hanada, K. (2024). aedl. R package: Almost-Exact Inference for the DerSimonian-Laird Test Statistic. [CRAN]

その他の情報はresearchmapをご覧ください。