Skip Logic - MQUAD Platform

Skip Logic controls whether a question is shown. A question with skip logic only appears when its conditions are met. This is different from Validation, which controls whether an entered answer is acceptable — a question hidden by skip logic is simply not presented at all.

In the underlying survey schema, skip logic is stored as the relevant field. In the designer, you configure it through Skip Logic.

Where to configure it

Open your survey in the Survey Designer.
Select the question in the canvas.
In the right-hand Properties panel, scroll to the Advanced section.
Click Skip Logic.

The Skip Logic Builder opens with two tabs:

Visual Builder — add conditions ("when age is greater than or equal to 18"), combine them with AND / OR, and nest groups of conditions.
Raw Expression — type the expression directly in a client-friendly format (see below).

The generated XPath expression is shown as you build, and it is validated against the server when you save. Questions with no conditions are always shown.

Scope rule: A question inside a group can only reference questions in its same group plus top-level questions. A top-level question cannot reference a question inside a group. This keeps skip logic predictable.

The two expression formats

Raw expression (what you type)

The Raw Expression tab uses a compact, client-friendly format:

age >= 18 & has_children = Yes

& means AND
| means OR
Values with spaces do not need quotes
Use parentheses for grouping: facility_type=Primary Health Centre&(region=North|region=South)

Internal format (what is stored)

The builder converts what you type into the internal XPath format that is stored with the question and evaluated at runtime:

${age} >= 18 and ${has_children} = 'Yes'

You will see the internal format in the Generated Expression preview. If you paste an existing XLSForm expression (the internal format), the builder parses it back into the visual builder automatically.

Simple equality

Show pregnancy questions only when the respondent's sex is female:

${sex} = 'female'

In the raw tab, the same rule reads sex = female.

Multiple conditions

AND — all conditions must be true

Show questions only when the respondent is female and of age:

${sex} = 'female' and ${age} >= 18

OR — any condition may be true

Show a section when either condition holds:

${district} = 'Mumbai' or ${district} = 'Pune'

Mixed AND / OR with parentheses

(${sex} = 'female' or ${sex} = 'trans_female') and ${age} >= 18

Numeric conditions

Show adult employment questions when age is 18 or older:

${age} >= 18

All comparison operators are available: =, !=, <, <=, >, >=.

Select-one questions

Show a "Specify other" question when Other is selected:

${employer_type} = 'other'

For a select-one, a simple equality works because exactly one option is chosen.

Select-multiple questions

For multi-select questions, use selected() to test a single option:

selected(${symptoms}, 'fever')

and count-selected() for the number of selected options:

count-selected(${symptoms}) >= 2

Note: selected() requires the option value (the variable name of the choice), not the displayed label.

Nested skip logic

Skip logic chains naturally. Question C can depend on Question B, which depends on Question A:

# Question A (no skip logic) — always shown
# Question B shown only when:
${consent} = 'yes'
# Question C shown only when BOTH:
${consent} = 'yes' and ${married} = 'yes'

When the answer that Question C depends on (e.g. consent) changes, MQUAD re-evaluates C's visibility immediately. Hiding a question does not erase an answer already entered for it — the value is retained (and re-shown if the question becomes visible again). If you need a hidden value to be cleared, add validation on the hidden question, or clear it by hand before submission.

Date-based skip logic

Calculations and date functions are valid inside relevance expressions:

date-diff('days', ${registration_date}, ${visit_date}) >= 30

Show the follow-up section when at least 30 days have passed since registration. See Date and Time Reference for the exact rules of date-diff.

Calculated-value-driven skip logic

Skip logic can depend on a calculated value:

${age} >= 18

where age is itself a calculated question:

age(${dob}, ${interview_date})

MQUAD's dependency graph re-evaluates calculations first, then re-evaluates relevance expressions that depend on them, so the section appears as soon as the age computation updates. See Auto-Populate and Calculations.

Common mistakes

Using the label instead of the variable name — sex = 'female' uses the variable name, not the displayed question text.
Missing quotes on string values — district = Mumbai may parse but won't match; use district = Mumbai in the raw tab (unquoted is accepted there) or 'Mumbai' in the internal format.
Testing a multi-select with = — a multi-select value can contain many options, so symptoms = 'fever' only matches when fever is the only selection. Use selected(${symptoms}, 'fever') instead.
Referencing a sibling-group question — questions inside a group can only reference same-group and top-level questions. Move the referenced question to the top level if needed.