IDENTIFYING OPPORTUNITIES FOR EARLIER DIAGNOSIS OF IDIOPATHIC PULMONARY FIBROSIS IN ROUTINE CARE IN THE UK: A RETROSPECTIVE CLINICAL COHORT STUDY (OPPORTUNITIES FOR EARLIER IPF DIAGNOSIS)

Study type

• Study topic:
  Disease /health condition
• Study type:
  Non-interventional study
• Scope of the study:
  Disease epidemiology
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Other
• Non-interventional study design, other:
  Observational, historical database study

Study drug and medical condition

• Medical condition to be studied:
  Idiopathic pulmonary fibrosis

Population studied

• Short description of the study population:
  • Patients who have a diagnostic for Idiopathic pulmonary fibrosis (IPF) between 1990 and 2015; • Have a minimum of 2 years continuous clinical records in the years immediately preceding their index diagnosis; • Aged 40 years or older at index date
• Age groups:
  Adults (18 to < 46 years)

  Adults (46 to < 65 years)

  Adults (65 to < 75 years)

  Adults (75 to < 85 years)

  Adults (85 years and over)
• Special population of interest:
  Other
• Special population of interest, other:
  Idiopathic pulmonary fibrosis (IPF) patients
• Estimated number of subjects:
  2000

Study design details

• Main study objective:
  With a view to identifying potential opportunities for earlier referral to specialists and (ultimately) earlier diagnosis of IPF, this study aims to:(i) Evaluate patients’ patterns of HRU in the years preceding their IPF diagnosis.(ii) Characterise the clinical features of patients at the time of their IPF diagnosis.
• Outcomes:
  1. Consultations including lower respiratory (LR) consultations2. Hospitalisations (in-patient attendances): same day or following 7 days3. Out patient visits with a code for a LR complaint (same day or following 7 days)4. Accident & Emergency attendances coded for a LR complaint (same day or following 7 days)5. Chest X-ray
• Data analysis plan:
  • The analysis will assess changes in HRU over the 25-year period (1990–2015), and in 5-year increments (0–5 years, 6–10 years, 11–15 years, 16–20 years and 21–25 years) • Summary statistics will be used to characterise patients at time of IPF diagnosis:o For variables measured on the interval or ratio scale, summary statistics produced will be:• Sample size (n)• Percentage non missing• Mean• Variance/standard deviation• Range (minimum- maximum)• Median• Inter-quantile range (25th and 75th percentile)o For categorical variable the summary statistics will include:• Sample size (n)• Range • Count and percentage by category (distribution)• Statistically significant results will be defined as p<0.05 and trends as 0.05≤p<0.10. • Suitable tests (e.g. F tests, t tests, χ2 tests) and models (e.g. linear models) will be used, as appropriate, to explore the interaction between different clinical characteristics and features (e.g. year, age) of diagnosis.