When & Why to Use

Call standard_screener() when you need a ready-made demographic screener that:

• Adds the core demo questions (age, gender, region, etc.) in the right order
• Weights the data to national census proportions for the chosen country
• Closes quotas automatically once the targets are met

Use it to jump-start GenPop surveys or any study that just needs a quick, balanced sample without hand-building the screener every time.

Supported Screeners

Country code	Available templates	Typical use-case
US	GenPop, NestedGenPop	General population or nested quotas
GB	GenPop, 16to54	UK GenPop or younger audience
AU	GenPop	Australian general population

Need something else? Register a new template in SCREENER_REGISTRY and it becomes instantly callable.

Function Signature

standard_screener(country: str, name: str = "GenPop") -> None

Arg	Type	Required	Default	Description
country	str	✓	-	ISO-style code used by MX8 Labs ("US", "GB", "AU", ...)
name	str	✗	"GenPop"	Template name listed in Supported Screeners

What Happens Under the Hood

1. Looks up the template in SCREENER_REGISTRY.
2. Injects the questions into the current survey (self).
3. Applies built-in quota weights so fieldwork stays on-target.

No return value; the survey object is modified in place.

Example Code

# US general population survey
s.standard_screener("US")

# UK younger audience, ages 16-54
s.standard_screener("GB", "16to54")

# Nested quotas in a US screener
s.standard_screener(country="US", name="NestedGenPop")

Notes & Tips

• Chainable - call other survey builders before or after; order doesn't matter.
• Extensible - create custom screeners by adding lambdas to SCREENER_REGISTRY.
• Idempotent - calling the same screener twice only adds one set of questions.
• Compliance - questions are locally adapted (e.g., ethnicity lists) to each market.

That's it. One line, instant, census-weighted screener.