Table 1 Definitions of “current asthma” and prevalence estimates computed using data from INAsma survey (n = 6257) and from NHANES 2009 (n = 10348)

Ever had asthma and wheeze in the last 12 months [13]

9.3 [8.8-10.0]

n.a.

Ever had asthma and this was confirmed by a physician and at least one in the last 12 months: wheeze, waking with tightness in the chest, waking with breathlessness, waking with cough [14]

8.5 [7.7-9.3]*

n.a.

Ever had asthma and at least one of 3 symptoms in the last 12 months: wheezing, waking with breathlessness or having an asthma attack [9]

10.3 [9.5-11.0]

n.a.

Ever had asthma and still have asthma [15, 16]

n.a.

n.a.

Ever had asthma and was this confirmed by a physician and wheeze and/or taking medication(s) for asthma or wheezing in the past 12 months [17]

n.a.

n.a.

At least one of the following: 1) Ever had asthma and was confirmed by a doctor and still have asthma or 2) significant bronchodilator response according to reversibility [18]

n.a.

n.a.

Ever had asthma and still have asthma and was confirmed by a physician [19]

n.a.

n.a.

At least one of the following: 1) Ever had asthma and wheezing in the last 12 months or 2) wheezing 4 times or more during the last 12 months or 3) physician diagnosis and wheezing in the last 12 months or 4) current use of inhalation steroids [20]

n.a.

n.a.

Diagnosed with asthma by a physician and wheeze in the last 12 months [21]

7.6 [6.9-8.3]*

1.7 [1.5-1.9]

Diagnosed with asthma by a physician and currently taking asthma medication [22]

7.4 [6.7-8.1]*

1.1 [0.9-1.3]

Diagnosed with asthma by a physician and use of asthma medication in the last 12 months and cough or wheeze in the last 12 months [23]

5.3 [4.7-5.9]^†

n.a.

Diagnosed with asthma by a physician and at least one: currently taking asthma medication, attacks of shortness of breath or recurrent wheeze in the last 12 months [24]

6.3 [5.6-6.0]*^,‡

n.a.

Diagnosed with asthma by a physician and still have asthma [25–37]

n.a.

8.4 [7.9-8.4]

Diagnosed with asthma by a physician and any of the following in the previous 2 years: wheezing following a common cold, dyspneal feeling at night or early in the morning, cough or wheeze during exercise [38]

n.a.

n.a.

Physician stated that (you) had asthma in the last 2 years or on 2 or more separate occasions had wheezing in the last 2 years [39, 40]

n.a.

n.a.

At least one of the following: 1) Diagnosed with asthma by a physician and at least 1 symptom in the last 12 months: wheeze, wheezes with attacks of shortness of breath, nocturnal attacks of shortness of breath, use of asthma medication or 2) reversible airways obstruction [41]

n.a.

n.a.

Wheeze in the last 12 months [42–54]

22.9 [21.9-23.9]

12.9 [12.2-13.5]

Wheeze in the last 12 months or currently taking asthma medication [55]

24.4 [23.3-25.5]

12.9 [12.2-13.5]

Current wheeze and 1 of the following: 1) ever had an asthma attack or 2) ever had asthma or 3) taking medication(s) for asthma or wheeze [56]

9.3 [8.6-10.0]**

n.a.

Asthma attack or currently taking asthma medication [2]

9.0 [8.3-9.7]

n.a.

At least one in the last 12 months: Waking at night by shortness of breath, had an asthma attack or currently taking any medicines (including inhalers, aerosols or tablets) for asthma [57]

14.5 [13.6-15.4]

n.a.

At least one of the following symptoms: wheeze in the last 12 months, coughing constantly for more than 3 weeks in any time in your life, attack of asthma in the last 12 months, or nasal allergies including hay fever in the last 12 months [58]

n.a.

17.2 [16.5-17.9]^‡‡

Wheeze in the last 12 months and at least 1 of the following in the last 12 months: any lifetime episode of asthma; wheezing during physical exercise; four or more episodes of wheezing in the previous year; or waking at night at least once a week due to wheezing [59]

n.a.

8.8 [8.3-9.3]^††

Asthma in the last 12 months [60–66]

n.a.

n.a.

Had a condition which causes difficulty in breathing, with wheezing noises in the chest in the last 12 months [67]

n.a.

n.a.

At least one of the following: 1) any symptom in the last 12 months: wheezing, shortness of breath, coughing bouts or dyspnea or 2) previous physician-based diagnosis of asthma or 3) use of medication for asthma [68]

n.a.

n.a.

Both: 1) Ever whistling sound from chest or chest tightness or breathlessness in the morning, and 2) having suffered from asthma or having an attack of asthma in the past 12 months or using bronchodilators [69]

n.a.

n.a.

Bronchial hyperresponsiveness and asthma symptoms (wheeze, night cough, or shortness of breath at rest) within the previous 12 months [70]

n.a.

n.a.

At least one of the following: 1) Recent symptoms (wheeze or nocturnal cough) or 2) asthma medication use [71]

39.5 [38.2-40.7]

n.a.