Loppow 2001.

Methods	Design: cross‐over, 4 weeks washout Randomisation: yes, method not stated Blinding: double‐blind Withdrawals: stated
Participants	Setting: single‐centre study, Germany, hospital outpatient clinic Number eligible: not stated Number enrolled: 19 Number in treatment group: 19 (cross‐over) Number in control group: 19 (cross‐over) Number of withdrawals (treatment/control): 0/0 Number completing trial (treatment/control): 19/19 Age range: 31 to 77 years Sex: 12 M, 7 F Ethnicity: not stated COPD diagnosis: chronic bronchitis (ATS criteria, cough and sputum production), current or ex‐smokers > 20 pack‐years Severity of COPD: mean FEV1 83.4% predicted (2 patients had no airflow obstruction) Inclusion criteria: as for COPD diagnosis; 14 patients had bronchial hyper‐responsiveness (PC20 methacholine < 8 mg/mL) Exclusion criteria: use of inhaled or systemic corticosteroids in previous 3 months, respiratory tract infection in previous 4 weeks Baseline characteristics of treatment/control groups: cross‐over study
Interventions	FP 1000 µg/day Placebo Delivery device not stated 4 weeks each treatment period (cross‐over)
Outcomes	FEV1 VC Exhaled NO Induced sputum cell count Induced sputum fluid‐phase markers (LCH, ECP, elastase, IL‐8, iNOS)
Notes	Chronic bronchitis patients included, not only COPD with airflow obstruction 14/19 patients had bronchial hyper‐responsiveness (PC20 MCh < 8 mg/mL) and 6/19 had positive skin prick test
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "randomised"
Allocation concealment (selection bias)	Unclear risk	Information not available
Blinding (performance bias and detection bias) All outcomes	Low risk	Quote: "double blind"
Incomplete outcome data (attrition bias) All outcomes	Low risk	No withdrawals
Selective reporting (reporting bias)	Low risk	All outcomes reported