Comparative screening performance of peak expiratory flow indicators for COPD and airflow limitati

Background and study objective

This retrospective comparative study aimed to evaluate the screening efficacy of different peak expiratory flow (PEF) evaluation indicators for chronic obstructive pulmonary disease (COPD) and to assess the consistency of various PEF metrics with FEV1% predicted when grading the severity of airflow limitation. The investigation was performed using clinical pulmonary function test results from patients suspected of COPD who underwent testing at a single center.

Study design and patient population

Investigators conducted a retrospective analysis of pulmonary function test data from 1,512 patients who were clinically suspected of COPD. These patients were tested in the Pulmonary Function Laboratory of China-Japan Friendship Hospital between May 2023 and May 2024. The study is reported as a comparative study published in Zhonghua Yi Xue Za Zhi (2026 Aug 25;106(31):3256–3263) with PMID 42618502 and DOI 10.3760/cma.j.cn112137-20251230-03481.

PEF and pulmonary function indicators analyzed

Collected pulmonary function parameters listed in the abstract include:

• Post-bronchodilator FEV1/FVC.
• Pre-bronchodilator FEV1 measured value as a percentage of predicted (FEV1% predicted).
• Multiple pre-bronchodilator PEF indicators: measured value, measured value divided by height2, and measured value expressed as % predicted.
• Multiple post-bronchodilator PEF indicators: measured value, measured value divided by height2, and measured value expressed as % predicted.

These variables were intended to be compared for two related purposes: (1) the ability of different PEF indicators to screen for impaired lung function consistent with COPD, and (2) the consistency of PEF indicators with FEV1% predicted when grading the severity of airflow limitation.

Statistical analysis approach

The abstract indicates that receiver operating characteristic (ROC) curve analysis was used to evaluate the screening performance of the different PEF indicators for detecting impaired lung function. ROC methodology is appropriate to assess discrimination (for example, via area under the curve or c-statistic) and to derive potential operating thresholds, but the abstract as provided is truncated before reporting any ROC statistics, area under the curve values, sensitivities, specificities, or chosen cutoffs.

Available reported findings and missing outcome data

The source text supplied here describes the study objective, sample size, study interval, list of pulmonary function variables collected, and the planned analytical approach (ROC curves). However, the abstract text in the provided source is truncated mid-sentence and does not include the numerical or categorical results, comparative diagnostic accuracy metrics, measures of agreement between PEF indicators and FEV1% predicted, or conclusions regarding which PEF indicators—if any—performed best for screening or severity assessment.

Because key outcome data are missing from the provided source excerpt, specific results such as AUC values, optimal thresholds, sensitivity/specificity pairs, or agreement statistics (kappa, correlation coefficients, etc.) cannot be restated here. Any interpretation about the relative screening performance or clinical recommendations would therefore require the full-text article or a complete abstract.

Implications, limitations, and need for full-text data

Implications:

• The study addresses a clinically relevant question: whether simple PEF measurements (including normalized forms such as PEF/height2 or % predicted) can effectively screen for COPD and reflect severity compared with FEV1% predicted, which is the standard metric for grading airflow limitation.

Limitations based on the available source:

• The abstract excerpt lacks outcome data, preventing assessment of diagnostic accuracy and the practical utility of the evaluated PEF indicators.
• Single-center retrospective design is described; the external validity and applicability to other populations were not reported in the provided excerpt.

Required next steps to complete interpretation:

• Review the full-text article to obtain ROC results (AUC/c-statistics), sensitivity/specificity, recommended thresholds, and measures of concordance with FEV1% predicted.
• Examine subgroup analyses (if present), methods for selecting predicted PEF values, and how height normalization was derived.

Bibliographic and publication details

• Journal: Zhonghua Yi Xue Za Zhi. 2026 Aug 25;106(31):3256–3263.
• PMID: 42618502. DOI: 10.3760/cma.j.cn112137-20251230-03481.
• Authors and affiliation: X P Li et al.; National Center for Respiratory Medicine, State Key Laboratory of Respiratory Health and Multimorbidity, National Clinical Research Center for Respiratory Diseases, Institute of Respiratory Medicine, Chinese Academy of Medical Sciences; Center of Respiratory Medicine, China-Japan Friendship Hospital, Department of Pulmonary and Critical Care Medicine, Beijing, China.

Note: This rewrite adheres to the information available in the provided PubMed source. The abstract text in the source was truncated before reporting diagnostic performance results and conclusions; therefore, specific outcome metrics and final recommendations were not available for extraction and are not included here. To obtain complete results and apply findings clinically, consult the full-text article linked through the journal or DOI.