title: [Variations in the diagnostic confirmation process between breast cancer mass screening units].
abstract: OBJECTIVE
  To analyse variations in the diagnostic confirmation process between screening units, variations in the outcome of each episode and the relationship between the use of the different diagnostic confirmation tests and the lesion detection rate.
  
  
  METHODS
  Observational study of variability of the standardised use of diagnostic and lesion detection tests in 34 breast cancer mass screening units participating in early-detection programmes in three Spanish regions from 2002-2011.
  
  
  RESULTS
  The diagnostic test variation ratio in percentiles 25-75 ranged from 1.68 (further appointments) to 3.39 (fine-needle aspiration). The variation ratio in detection rates of benign lesions, ductal carcinoma in situ and invasive cancer were 2.79, 1.99 and 1.36, respectively. A positive relationship between rates of testing and detection rates was found with fine-needle aspiration-benign lesions (R(2): 0.53), fine-needle aspiration-invasive carcinoma (R(2): 0 28), core biopsy-benign lesions (R(2): 0.64), core biopsy-ductal carcinoma in situ (R(2): 0.61) and core biopsy-invasive carcinoma (R(2): 0.48).
  
  
  CONCLUSIONS
  Variation in the use of invasive tests between the breast cancer screening units participating in early-detection programmes was found to be significantly higher than variations in lesion detection. Units which conducted more fine-needle aspiration tests had higher benign lesion detection rates, while units that conducted more core biopsies detected more benign lesions and cancer.
authors.affiliation: Servicio de Salud del Principado de Asturias, Oviedo (Asturias), España. Electronic address: carmen.natal@sespa.es.
authors.forename: Carmen
authors.initials: C
authors.lastname: Natal
authors.affiliation: CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Madrid, España; Universidad de Oviedo, Oviedo (Asturias), España; IUOPA-Área de Medicina Preventiva y Salud Pública, Departamento de Medicina, Universidad de Oviedo, Asturias, España.
authors.forename: Ana
authors.initials: A
authors.lastname: Fernández-Somoano
authors.affiliation: IUOPA-Área de Medicina Preventiva y Salud Pública, Departamento de Medicina, Universidad de Oviedo, Asturias, España; Departamento de Epidemiología y Evaluación, IMIM (Hospital del Mar Instituto de Investigación Médica) y Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Barcelona, España.
authors.forename: Isabel
authors.initials: I
authors.lastname: Torá-Rocamora
authors.affiliation: CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Madrid, España; Universidad de Oviedo, Oviedo (Asturias), España.
authors.forename: Adonina
authors.initials: A
authors.lastname: Tardón
authors.affiliation: IUOPA-Área de Medicina Preventiva y Salud Pública, Departamento de Medicina, Universidad de Oviedo, Asturias, España; Departamento de Epidemiología y Evaluación, IMIM (Hospital del Mar Instituto de Investigación Médica) y Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Barcelona, España.
authors.forename: Xavier
authors.initials: X
authors.lastname: Castells
mesh_terms: D044963:Biopsy, Fine-Needle / Q000706:statistics & numerical data*; D062005:Biopsy, Large-Core Needle / Q000706:statistics & numerical data*; D001940:Breast / Q000473:pathology; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D002278:Carcinoma in Situ / Q000175:diagnosis* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006801:Humans; D008403:Mass Screening / Q000592:standards / Q000706:statistics & numerical data*
keywords: Análisis de áreas pequeñas; Assessment of health services; Breast cancer; Clinical practice variation; Cáncer de mama; Detección precoz de cáncer; Diagnostic techniques and procedures; Early detection of cancer; Evaluación de servicios sanitarios; Small area variation analysis; Técnicas y procedimientos diagnósticos; Variaciones en la práctica médica