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A predictive scoring instrument for tuberculosis lost to follow-up outcome

Teresa Rodrigo11223*, Joan A Caylà11223, Martí Casals11215, José Mª García-García14, José A Caminero1145, Juan Ruiz-Manzano1136, Rafael Blanquer17, Rafael Vidal1138, Neus Altet19, José L Calpe110, Antón Penas111 and Working Group on Completion of Tuberculosis Treatment in Spain

Author Affiliations

1 Programa Integrado de Investigación en Tuberculosis (PII TB) de la Sociedad Española de Neumología y Cirugía Torácica (SEPAR), Barcelona, Spain

2 Unidad de Investigación de Tuberculosis de Barcelona, Servicio de Epidemiología de la Agencia de Salud Pública de Barcelona, Barcelona, Spain

3 Fundación Respira de la SEPAR, Barcelona, Spain

4 Hospital San Agustín, Avilés, Asturias, Spain

5 Hospital General Universitario de Gran Canaria Dr. Negrín, Canary Islands, Spain

6 Hospital Universitario Germans Trías y Pujol de Badalona, Badalona, Spain

7 Hospital Universitario Dr. Peset de Valencia, Valencia, Spain

8 Hospital Vall D'Hebrón de Barcelona, Barcelona, Spain

9 Unidad de Prevención y Control de Tuberculosis de Barcelona, Barcelona, Spain

10 Hospital Marina Baixa de Alicante, Alicante, Spain

11 Complejo Hospitalario Xeral-Calde, Lugo, Spain

12 Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain

13 CIBER de Enfermedades Respiratorias (CIBERES), Barcelona, Spain

14 International Union Against Tuberculosis and Lung Disease, París, France

15 Departament de Salut Pública, Universitat de Barcelona, Barcelona, Spain

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Respiratory Research 2012, 13:75  doi:10.1186/1465-9921-13-75

Published: 2 September 2012



Adherence to tuberculosis (TB) treatment is troublesome, due to long therapy duration, quick therapeutic response which allows the patient to disregard about the rest of their treatment and the lack of motivation on behalf of the patient for improved. The objective of this study was to develop and validate a scoring system to predict the probability of lost to follow-up outcome in TB patients as a way to identify patients suitable for directly observed treatments (DOT) and other interventions to improve adherence.


Two prospective cohorts, were used to develop and validate a logistic regression model. A scoring system was constructed, based on the coefficients of factors associated with a lost to follow-up outcome. The probability of lost to follow-up outcome associated with each score was calculated. Predictions in both cohorts were tested using receiver operating characteristic curves (ROC).


The best model to predict lost to follow-up outcome included the following characteristics: immigration (1 point value), living alone (1 point) or in an institution (2 points), previous anti-TB treatment (2 points), poor patient understanding (2 points), intravenous drugs use (IDU) (4 points) or unknown IDU status (1 point). Scores of 0, 1, 2, 3, 4 and 5 points were associated with a lost to follow-up probability of 2,2% 5,4% 9,9%, 16,4%, 15%, and 28%, respectively. The ROC curve for the validation group demonstrated a good fit (AUC: 0,67 [95% CI; 0,65-0,70]).


This model has a good capacity to predict a lost to follow-up outcome. Its use could help TB Programs to determine which patients are good candidates for DOT and other strategies to improve TB treatment adherence.

Lost to follow-up outcome; Scoring system; Tuberculosis; Adherence; Predictors