A novel scoring system to measure radiographic abnormalities and related spirometric values in cured pulmonary tuberculosis

PLoS One. 2013 Nov 1;8(11):e78926. doi: 10.1371/journal.pone.0078926. eCollection 2013.

Abstract

Background: Despite chemotherapy, patients with cured pulmonary tuberculosis may result in lung functional impairment.

Objective: To evaluate a novel scoring system based on the degree of radiographic abnormalities and related spirometric values in patients with cured pulmonary tuberculosis.

Methods: One hundred and twenty seven patients with cured pulmonary tuberculosis were prospectively enrolled in a referral hospital specializing in respiratory diseases. Spirometry was performed and the extent of radiographic abnormalities was evaluated twice by each of two readers to generate a novel quantitative score. Scoring reproducibility was analyzed by the intra-class correlation coefficient (ICC) and the Bland-Altman method. Multiple linear regression models were performed to assess the association of the extent of radiographic abnormalities with spirometric values.

Results: The intra-observer agreement for scoring of radiographic abnormalities (SRA) showed an ICC of 0.81 (CI:95%, 0.67-0.95) and 0.78 (CI:95%, 0.65-0.92), for reader 1 and 2, respectively. Inter-observer reproducibility for the first measurement was 0.83 (CI:95%, 0.71-0.95), and for the second measurement was 0.74 (CI:95%, 0.58-0.90). The Bland-Altman analysis of the intra-observer agreement showed a mean bias of 0.87% and -0.55% and an inter-observer agreement of -0.35% and -1.78%, indicating a minor average systematic variability. After adjustment for age, gender, height, smoking status, pack-years of smoking, and degree of dyspnea, the scoring degree of radiographic abnormalities was significantly and negatively associated with absolute and percent predicted values of FVC: -0.07 (CI:95%, -0.01 to -0.04); -2.48 (CI:95%, -3.45 to -1.50); and FEV1 -0.07 (CI:95%, -0.10 to -0.05); -2.92 (CI:95%, -3.87 to -1.97) respectively, in the patients studied.

Conclusion: The extent of radiographic abnormalities, as evaluated through our novel scoring system, was inversely associated with spirometric values, and exhibited good reliability and reproducibility. As intra-observer and inter-observer agreement of the SRA varied from good to excellent, the use of SRA in this setting appears acceptable.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Female
  • Humans
  • Linear Models
  • Lung / diagnostic imaging
  • Lung / drug effects
  • Lung / physiopathology
  • Male
  • Middle Aged
  • Observer Variation
  • Outcome Assessment, Health Care / methods
  • Outcome Assessment, Health Care / statistics & numerical data
  • Radiography / methods*
  • Respiratory Function Tests
  • Spirometry / methods*
  • Tuberculosis, Pulmonary / diagnostic imaging*
  • Tuberculosis, Pulmonary / drug therapy
  • Tuberculosis, Pulmonary / physiopathology*

Grant support

The study was sponsored by the Instituto Nacional de Enfermedades Respiratorias, Secretaría de Salud, Mexico City. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.