The Traffic-Light Scheme for Asthma Control Assessment
The traffic-light scheme classifies asthma control into three color-coded categories—green (well-controlled), yellow (not well-controlled), and red (very poorly controlled)—to guide therapy adjustments through a stepwise approach. This system provides a clear, actionable framework for both clinicians and patients to recognize when asthma is adequately managed versus when treatment intensification is needed 1, 2.
How the Traffic-Light System Works
The classification is based on the most severe impairment or risk category across multiple assessment domains. If any single parameter falls into a worse category, that determines the overall control level 3.
Green Zone: Well-Controlled Asthma
For patients ≥12 years old, well-controlled asthma means 1:
- Symptoms: ≤2 days per week
- Nighttime awakenings: ≤2 times per month
- SABA use for symptom relief: ≤2 days per week (excluding pre-exercise use)
- Activity limitation: None
- Lung function: FEV₁ or peak flow >80% predicted/personal best
- Exacerbations: 0-1 per year requiring oral corticosteroids
Action: Maintain current treatment step. Schedule follow-up every 1-6 months. Consider stepping down therapy if control maintained for ≥3 months 1, 3.
Yellow Zone: Not Well-Controlled Asthma
This intermediate category indicates inadequate control 1:
- Symptoms: >2 days per week
- Nighttime awakenings: 1-3 times per week
- SABA use: >2 days per week
- Activity limitation: Some limitation present
- Lung function: 60-80% predicted/personal best
- Exacerbations: ≥2 per year
Action: Step up at least one treatment step and reassess in 2-6 weeks. Review medication adherence, inhaler technique, and environmental triggers before escalating 3.
Red Zone: Very Poorly Controlled Asthma
This represents dangerous, inadequate control 1, 2:
- Symptoms: Throughout the day
- Nighttime awakenings: ≥4 times per week
- SABA use: Several times per day
- Activity limitation: Extremely limited
- Lung function: <60% predicted/personal best
- Exacerbations: ≥2 per year
Action: Consider short course of oral corticosteroids immediately. Step up 1-2 treatment steps. Reassess in 2 weeks. Consider alternative diagnoses if no improvement 1, 3.
Age-Specific Variations
The thresholds differ for children 2, 3:
Ages 0-4 years:
- Well-controlled: ≤2 days/week symptoms, ≤1 nighttime awakening/month, 0-1 exacerbations/year
- Not well-controlled: >2 days/week symptoms, >1 awakening/month, 2-3 exacerbations/year
- Very poorly controlled: Daily symptoms, >1 awakening/week, >3 exacerbations/year
Ages 5-11 years:
- Similar to adults but with FEV₁/FVC ratio considerations (>80% for well-controlled, <75% for very poorly controlled)
Critical Implementation Points
Assessment frequency matters: Schedule visits every 2-6 weeks when initiating therapy or stepping up treatment. Once control is achieved, extend to 1-6 month intervals 3.
Multiple measures are essential because different parameters assess different disease manifestations and may not correlate. A patient can have normal lung function but still experience frequent exacerbations, placing them in a worse control category 3.
Common pitfall: Patients and clinicians often overestimate control 4. Many patients accept ongoing symptoms as "normal" for asthma when they actually represent inadequate control. Use validated questionnaires (ACT score ≥20 indicates well-controlled) to supplement clinical assessment 2.
The risk domain is independent of impairment: A patient may have minimal day-to-day symptoms but remain at high risk for severe exacerbations based on history, requiring continued aggressive therapy 3.
Stepwise Therapy Adjustments
The traffic-light assessment directly determines treatment steps 3:
- Green → Maintain or step down (if stable ≥3 months)
- Yellow → Step up one level
- Red → Step up 1-2 levels + consider oral corticosteroids
Before stepping up therapy in the yellow or red zones, verify medication adherence, proper inhaler technique, and address environmental triggers or comorbidities (GERD, rhinitis, obesity) that may impede control 3.
Never treat with SABA alone: All patients require ICS-containing therapy to reduce exacerbation risk, even those with seemingly mild symptoms 5, 6.