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Article ; Online: Sample size calculation for clinical trials analyzed with the meta-analytic-predictive approach.

Qi, Hongchao / Rizopoulos, Dimitris / van Rosmalen, Joost

2023 Volume 14, Issue 3, Page(s) 396–413

Abstract: The meta-analytic-predictive (MAP) approach is a Bayesian method to incorporate historical controls in new trials that aims to increase the statistical power and reduce the required sample size. Here we investigate how to calculate the sample size of the ...

Abstract	The meta-analytic-predictive (MAP) approach is a Bayesian method to incorporate historical controls in new trials that aims to increase the statistical power and reduce the required sample size. Here we investigate how to calculate the sample size of the new trial when historical data is available, and the MAP approach is used in the analysis. In previous applications of the MAP approach, the prior effective sample size (ESS) acted as a metric to quantify the number of subjects the historical information is worth. However, the validity of using the prior ESS in sample size calculation (i.e., reducing the number of randomized controls by the derived prior ESS) is questionable, because different approaches may yield different values for prior ESS. In this work, we propose a straightforward Monte Carlo approach to calculate the sample size that achieves the desired power in the new trial given available historical controls. To make full use of the available historical information to simulate the new trial data, the control parameters are not taken as a point estimate but sampled from the MAP prior. These sampled control parameters and the MAP prior based on the historical data are then used to derive the statistical power for the treatment effect and the resulting required sample size. The proposed sample size calculation approach is illustrated with real-life data sets with different outcomes from three studies. The results show that this approach to calculating the required sample size for the MAP analysis is straightforward and generic.
MeSH term(s)	Humans ; Sample Size ; Models, Statistical ; Bayes Theorem ; Monte Carlo Method ; Research Design ; Computer Simulation
Language	English
Publishing date	2023-01-14
Publishing country	England
Document type	Meta-Analysis ; Journal Article
ZDB-ID	2548499-0
ISSN	1759-2887 ; 1759-2879
ISSN (online)	1759-2887
ISSN	1759-2879
DOI	10.1002/jrsm.1618
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: High-Precision Photoacoustic Nitrogen Dioxide Gas Analyzer for Fast Dynamic Measurement.

Qi, Hongchao / Zhang, Guangyin / Xu, Lin / Yang, Ling / Wang, Zhengzhi / Xu, Yufu / Chen, Ke

Analytical chemistry

2024 Volume 96, Issue 3, Page(s) 1354–1361

Abstract: A high-precision photoacoustic (PA) gas analyzer for fast dynamic measurement of ambient nitrogen dioxide ( ... ...

Abstract	A high-precision photoacoustic (PA) gas analyzer for fast dynamic measurement of ambient nitrogen dioxide (NO
Language	English
Publishing date	2024-01-09
Publishing country	United States
Document type	Journal Article
ZDB-ID	1508-8
ISSN	1520-6882 ; 0003-2700
ISSN (online)	1520-6882
ISSN	0003-2700
DOI	10.1021/acs.analchem.3c05084
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Article ; Online: Rapid Photoacoustic Exhaust Gas Analyzer for Simultaneous Measurement of Nitrogen Dioxide and Sulfur Dioxide.

Qi, Hongchao / Zhao, Xinyu / Xu, Yufu / Yang, Ling / Liu, Junjun / Chen, Ke

Analytical chemistry

2024 Volume 96, Issue 13, Page(s) 5258–5264

Abstract: A rapid photoacoustic (PA) exhaust gas analyzer is presented for simultaneous measurements of nitrogen dioxide ( ... ...

Abstract	A rapid photoacoustic (PA) exhaust gas analyzer is presented for simultaneous measurements of nitrogen dioxide (NO
Language	English
Publishing date	2024-03-19
Publishing country	United States
Document type	Journal Article
ZDB-ID	1508-8
ISSN	1520-6882 ; 0003-2700
ISSN (online)	1520-6882
ISSN	0003-2700
DOI	10.1021/acs.analchem.3c05936
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Article ; Online: Fiber-Optic Photoacoustic CO Sensor for Gas Insulation Equipment Monitoring Based on Cantilever Differential Lock-In Amplification and Optical Excitation Enhancement.

Zhao, Xinyu / Ma, Fengxiang / Wang, Heng / Qi, Hongchao / Li, Chenxi / Guo, Min / Chen, Ke

Analytical chemistry

2024 Volume 96, Issue 13, Page(s) 5298–5306

Abstract: A fiber-optic photoacoustic CO sensor for gas insulation equipment is proposed, which relies on F-P interferometric cantilever-based differential lock-in amplification and optical multipass excitation enhancement. The sensor has excellent characteristics ...

Abstract	A fiber-optic photoacoustic CO sensor for gas insulation equipment is proposed, which relies on F-P interferometric cantilever-based differential lock-in amplification and optical multipass excitation enhancement. The sensor has excellent characteristics of high sensitivity, antielectromagnetic interference, fast response, and long-distance detection. The photoacoustic pressure waves in the two resonators of the differential photoacoustic cell (DPAC) are simultaneously detected by two fiber-optic interferometric cantilevers and processed differentially; thereby, the gas flow noise is effectively suppressed. Based on the comprehensive analysis of the superposition of photoacoustic excitation and multipass absorption, the diameter of the resonator is determined to be 6 mm. The optical power emitted by the 1566.6 nm distributed feedback laser is increased to 500 mW by an erbium-doped fiber amplifier. The near-infrared light is reflected 30 times in the multipass cell, which improves the order of magnitude of optical effective excitation. Due to the low sound velocity of SF
Language	English
Publishing date	2024-03-20
Publishing country	United States
Document type	Journal Article
ZDB-ID	1508-8
ISSN	1520-6882 ; 0003-2700
ISSN (online)	1520-6882
ISSN	0003-2700
DOI	10.1021/acs.analchem.4c00233
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Article ; Online: Differential Cantilever Enhanced Fiber-Optic Photoacoustic Sensor for Diffusion Gas Detection.

Li, Chenxi / Zhang, Yajie / Guo, Min / Qi, Hongchao / Zhao, Xinyu / Chen, Ke

Analytical chemistry

2024 Volume 96, Issue 11, Page(s) 4562–4569

Abstract: Aiming at the problem of the fiber-optic photoacoustic (PA) sensor being easily disturbed by external vibration and noise, a differential cantilever enhanced fiber-optic PA sensor is proposed for diffusion gas detection. The sensor comprises two PA tubes ...

Abstract	Aiming at the problem of the fiber-optic photoacoustic (PA) sensor being easily disturbed by external vibration and noise, a differential cantilever enhanced fiber-optic PA sensor is proposed for diffusion gas detection. The sensor comprises two PA tubes with the same structure and a pair of differential interferometric cantilevers. The two PA tubes are symmetrically distributed. The laser is incident on the PA tube as the signal channel to excite the PA pressure wave. Another tube without incident laser is used as the reference channel to suppress external disturbance. The external interference signals and PA signals superimposed with disturbance are detected by the differential cantilevers from the two channels. The signals are simultaneously restored by a single white-light interferometry demodulator, which multiplexed the spectral frequency domain of the superimposed interference spectrum. The experimental results show that the suppression effect of the differential cantilever enhanced PA sensor on ambient noise is improved by 80%, compared to the traditional single-cantilever sensor. The external cofrequency disturbance is suppressed by 20.9 dB. The minimum detection limit to acetylene (C
Language	English
Publishing date	2024-03-07
Publishing country	United States
Document type	Journal Article
ZDB-ID	1508-8
ISSN	1520-6882 ; 0003-2700
ISSN (online)	1520-6882
ISSN	0003-2700
DOI	10.1021/acs.analchem.3c05396
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Article ; Online: Dense Multibutterfly Spots-Enhanced Miniaturized Optical Fiber Photoacoustic Gas Sensor.

Zhao, Xinyu / Qi, Hongchao / Wang, Heng / Wang, Xiaona / Guo, Min / Peng, Wei / Chen, Ke

Analytical chemistry

2024 Volume 96, Issue 14, Page(s) 5554–5559

Abstract: A miniaturized optical fiber photoacoustic gas sensor enhanced by dense multibutterfly spots is reported for the first time. The principle of space light transmission of neglecting paraxial approximation is theoretically analyzed for designing a dense ... ...

Abstract	A miniaturized optical fiber photoacoustic gas sensor enhanced by dense multibutterfly spots is reported for the first time. The principle of space light transmission of neglecting paraxial approximation is theoretically analyzed for designing a dense multibutterfly spots-based miniature multipass cell. In a multipass photoacoustic tube with a diameter of 16 mm, the light beam is reflected about a hundred times. The light spots on the mirror surfaces at both ends of the photoacoustic tube form a dense multibutterfly distribution. The volume of the micro multipass gas chamber is only 5.3 mL. An optical fiber cantilever based on F-P interference is utilized as a photoacoustic pressure detector. Compared with that of the single-pass structure, the gas detection ability of the photoacoustic system with dense multibutterfly spots is improved by about 50 times. The proposed miniaturized sensor realizes a detection limit of 3.4 ppb for C
Language	English
Publishing date	2024-03-28
Publishing country	United States
Document type	Journal Article
ZDB-ID	1508-8
ISSN	1520-6882 ; 0003-2700
ISSN (online)	1520-6882
ISSN	0003-2700
DOI	10.1021/acs.analchem.4c00005
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Article ; Online: Female Reproductive Factors and Risk of New-Onset Heart Failure: Findings From UK Biobank.

Zhu, Fang / Qi, Hongchao / Bos, Maxime / Boersma, Eric / Kavousi, Maryam

JACC. Heart failure

2023 Volume 11, Issue 9, Page(s) 1203–1212

Abstract: Background: A comprehensive evaluation of woman-specific risk factors in relation to incident heart failure (HF) is limited.: Objectives: This study sought to investigate the association of multiple female reproductive factors with the risk of HF.: ...

Abstract	Background: A comprehensive evaluation of woman-specific risk factors in relation to incident heart failure (HF) is limited. Objectives: This study sought to investigate the association of multiple female reproductive factors with the risk of HF. Methods: Between 2007 and 2010, 229,026 women (mean age: 56.5 years) without prevalent HF from the UK Biobank cohort were included and followed until December 2020. The relation between (self-reported) reproductive factors and HF was analyzed using Cox proportional hazards models with adjustment for potential confounding. Results: Menarche at age <12 years, compared to age 12-13 years, carried a 9% larger risk of HF (HR: 1.09 [95% CI: 1.01-1.18]). Younger age at menopause was associated with a higher risk of HF (HR Conclusions: The findings emphasize the importance of female reproductive history in the assessment of HF risk.
MeSH term(s)	Child ; Humans ; Female ; Middle Aged ; Adolescent ; Young Adult ; Adult ; Heart Failure/epidemiology ; Prospective Studies ; Reproductive History ; Biological Specimen Banks ; Risk Factors ; United Kingdom/epidemiology
Language	English
Publishing date	2023-04-19
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2705621-1
ISSN	2213-1787 ; 2213-1779
ISSN (online)	2213-1787
ISSN	2213-1779
DOI	10.1016/j.jchf.2023.02.019
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Article ; Online: Incorporating historical control information in ANCOVA models using the meta-analytic-predictive approach.

Qi, Hongchao / Rizopoulos, Dimitris / van Rosmalen, Joost

Research synthesis methods

2022 Volume 13, Issue 6, Page(s) 681–696

Abstract: The meta-analytic-predictive (MAP) approach is a Bayesian meta-analytic method to synthesize and incorporate information from historical controls in the analysis of a new trial. Classically, only a single parameter, typically the intercept or rate, is ... ...

Abstract	The meta-analytic-predictive (MAP) approach is a Bayesian meta-analytic method to synthesize and incorporate information from historical controls in the analysis of a new trial. Classically, only a single parameter, typically the intercept or rate, is assumed to vary across studies, which may not be realistic in more complex models. Analysis of covariance (ANCOVA) is often used to analyze trials with a pretest-posttest design, where both the intercept and the baseline effect (coefficient of the outcome at baseline) affect the estimated treatment effect. We extended the MAP approach to ANCOVA, to allow for variation in the intercept and the baseline effect across studies, and possibly also correlation between these parameters. The method was illustrated using data from the Alzheimer's Disease Cooperative Study (ADCS) and assessed with a simulation study. In the ADCS data, the proposed multivariate MAP approach yielded a prior effective sample size of 79 and 58 for the intercept and the baseline effect respectively and reduced the posterior standard deviation of the treatment effect by 12.6%. The result was robust to the choice of prior for the between-study variation. In the simulations, the proposed approach yielded power gains with a good control of the type I error rate. Ignoring the between-study correlation of the parameters or assuming no variation in the baseline effect generally led to less power gain. In conclusion, the MAP approach can be extended to a multivariate version for ANCOVA, which may improve the estimation of the treatment effect.
MeSH term(s)	Bayes Theorem ; Models, Statistical ; Sample Size ; Research Design ; Computer Simulation
Language	English
Publishing date	2022-04-26
Publishing country	England
Document type	Meta-Analysis ; Journal Article
ZDB-ID	2548499-0
ISSN	1759-2887 ; 1759-2879
ISSN (online)	1759-2887
ISSN	1759-2879
DOI	10.1002/jrsm.1561
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Ultrahigh-speed phase demodulation of a Fabry-Perot sensor based on fiber array parallel spectral detection.

Li, Chenxi / Qi, Hongchao / Han, Xiao / Zhao, Xinyu / Zhang, Yajie / Huang, Jiayu / Peng, Wei / Chen, Ke

Optics letters

2024 Volume 49, Issue 3, Page(s) 714–717

Abstract: An ultrahigh-speed phase demodulation system was designed for the Fabry-Perot (F-P) interferometric sensor based on fiber array parallel spectral detection. A high-power amplified spontaneous emission (ASE) source served as the broadband detection light. ...

Abstract	An ultrahigh-speed phase demodulation system was designed for the Fabry-Perot (F-P) interferometric sensor based on fiber array parallel spectral detection. A high-power amplified spontaneous emission (ASE) source served as the broadband detection light. The spectrum generated by the dispersion of the F-P interference light through an arrayed waveguide grating (AWG) was incident into the fiber array and was detected in parallel by 48 photodiodes. The 48-channel signals were acquired synchronously and processed in real time to achieve a phase demodulation for the F-P cavity at 200 kHz. As a result, a low-resolution spectral detection and demodulation system was constructed with high speed. The length demodulation range of the F-P cavity was 60-700 µm, and the demodulation resolution was as high as 0.22 nm. The designed high-sensitivity demodulator is expected to be used for ultrasonic and high-frequency vibration detection.
Language	English
Publishing date	2024-02-01
Publishing country	United States
Document type	Journal Article
ISSN	1539-4794
ISSN (online)	1539-4794
DOI	10.1364/OL.511903
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Article ; Online: Ultrahigh Sensitive Trace Gas Sensing System with Dual Fiber-Optic Cantilever Multiplexing-Based Differential Photoacoustic Detection.

Zhao, Xinyu / Wang, Zhengzhi / Li, Chenxi / Wang, Heng / Qi, Hongchao / Guo, Min / Ma, Fengxiang / Chen, Ke

Analytical chemistry

2024 Volume 96, Issue 3, Page(s) 1046–1053

Abstract: An ultrahigh sensitive trace gas sensing system was presented with dual cantilever-based differential photoacoustic detection. By combining the double enhancement of multipass absorption and optical differential detection, the gas detection sensitivity ... ...

Abstract	An ultrahigh sensitive trace gas sensing system was presented with dual cantilever-based differential photoacoustic detection. By combining the double enhancement of multipass absorption and optical differential detection, the gas detection sensitivity was significantly improved. The dual-channel synchronous photoacoustic detection was realized by fiber-optic Fabry-Perot interference spectrum multiplexing. The photoacoustic signals detected by two fiber-optic cantilever microphones installed in a differential photoacoustic cell (DPAC) were out of phase, while the detected gas flow noises were in phase. The optical differential detection method achieved both highly sensitive optical interference measurement and differential noise suppression. In the multipass configuration, the interaction path between excitation light and target gas achieved 4.1 m, which improved the photoacoustic signal by an order of magnitude compared with a single reflection. The maximum gas flow allowed by the system based on the DPAC was 250 sccm, which realized the dynamic monitoring of H
Language	English
Publishing date	2024-01-09
Publishing country	United States
Document type	Journal Article
ZDB-ID	1508-8
ISSN	1520-6882 ; 0003-2700
ISSN (online)	1520-6882
ISSN	0003-2700
DOI	10.1021/acs.analchem.3c03636
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