Clinical features

• cough ^b and any recent increase ^d
•   wheezing ^b and any recent increase ^d
• exertional dyspnoea ^b   
• sputum production ^b   and any recent increase or purulence ^d  

Why?

A history of wheezing, sputum production and severe exertional dyspnoea make COPD more likely

Patient	Target Disorder and Reference Standard	Diagnostic Test	LR+ (95% CI)	Post-test Probability	LR- (95% CI)	Post-test Probability
suspected COPD a    (pre-test probability: 9%)	COPD (spirometry)	sputum production ≥¼ cup per day	4.0	28%	0.84	8%
suspected COPD a (pre-test probability: 9%)	COPD (spirometry)	symptoms of chronic bronchitis	3.8 (2.0 to 7.2)	27%	0.66 (0.53 to 0.81)	6%
suspected COPD (pre-test probability: 9%)	COPD   (spirometry)	history of wheezing	3.1 (1.9 to 5.2)	23%	0.58 (0.45 to 0.75)	5%
suspected COPD a (pre-test probability: 9%)	COPD (spirometry)	severe exertional dyspnoea (grade IV)	3.0	23%	0.98	9%
suspected COPD a (pre-test probability: 9%)	COPD (spirometry)	cough	1.8 (1.2 to 2.6)	15%	0.69 (0.52 to 0.90)	6%
suspected COPD (pre-test probability: 9%)	COPD (spirometry)	any dyspnoea	1.2 (1.0 to 1.5)	11%	0.55 (0.31 to 0.98)	5%

Symptoms of bronchitis and daily wheeze increase the risk of COPD exacerbations

Patient	Prognostic Factor	Outcome	CER	OR (95% CI)	NNF+ (95% CI)
COPD b	daily wheeze independent	3 or more exacerbations of COPD at 12 months	46% (34% to 57%)	1.34	14
COPD	symptoms of bronchitis independent	3 or more exacerbations of COPD at 12 months	46% (34% to 57%)	1.56	9