Observation Methods

sight·line supports all eight standard behavioral observation methods used in school psychology and ABA practice. Each method is suited to different assessment questions — choosing the right one before you start recording produces more defensible data and less post-session rework.

Whole Interval Recording

Behavior is scored only if it occurs throughout the entire interval without stopping. If the behavior pauses even briefly, the interval is not scored.

When to use it: When you want a conservative estimate of behavior — useful for behaviors you want to show are high-rate or pervasive. Common for on-task observation when you need to demonstrate that a student was consistently engaged.

See Interval Recording for detailed guidance on whole interval setup, scoring, and interpretation.

Partial Interval Recording

Behavior is scored if it occurs at any point during the interval, regardless of how briefly.

When to use it: Useful for capturing low-rate or short-duration behaviors that might be missed by whole interval recording. Common for off-task behavior, stereotypy, or verbal outbursts.

See Interval Recording for detailed guidance on partial interval setup, scoring, and interpretation.

Momentary Time Sampling (MTS)

The timer pauses at the end of each interval. You observe what the student is doing at that exact moment and score accordingly, then resume the timer.

When to use it: A practical choice for naturalistic classroom observation when you can’t watch continuously — especially for behaviors that are relatively stable over time (on-task engagement, proximity, activity engagement). Also useful when you’re observing multiple students in alternating sequences.

See Interval Recording for detailed guidance on MTS setup, scoring, and interpretation.

Frequency / Event Recording

Count every occurrence of the target behavior within each interval. sight·line calculates rate automatically (occurrences per minute or per hour).

When to use it: Best for discrete behaviors with a clear start and end point — hand raises, call-outs, physical contacts, transitions, or any behavior where total count matters. Not well-suited for behaviors with unclear boundaries or highly variable duration.

See Frequency Recording for detailed guidance on setup, scoring, and interpretation.

ABC Recording

Log each behavioral event as an Antecedent → Behavior → Consequence sequence. sight·line calculates conditional probabilities across events and sessions to help identify behavioral function.

When to use it: Foundational for functional behavior assessment (FBA). Use when you need to understand what triggers behavior and what maintains it — not just how often it occurs. Most useful after you have a hypothesis about function and want to test it systematically.

See ABC Recording for detailed guidance on setting up tag sets, recording entries, and interpreting function patterns.

Narrative Recording

Write free-form, timestamped observations throughout the session. No structured coding — just clinical impressions, environmental details, and contextual notes.

When to use it: Best for initial observations when you don’t yet know which behaviors to target, for capturing classroom dynamics and setting factors, or for documenting qualitative clinical impressions alongside quantitative data from other methods. Narrative data often provides the contextual detail that makes quantitative data meaningful to IEP teams.

See Narrative Recording for detailed guidance on chronological note-taking, contextual documentation, and synthesizing narrative data.

Duration Recording

Measure how long each behavioral episode lasts using start/stop toggles. sight·line tracks each episode individually and computes total duration, average episode length, and percentage of observation time.

When to use it: When the length of behavior matters more than how many times it occurs. Appropriate for tantrums, crying episodes, sustained engagement, out-of-seat behavior, or any behavior where intensity is better captured by time than count.

See Duration Recording for detailed guidance on setup, episode tracking, and interpreting time-based data.

Latency Recording

Measure the time from a prompt or instruction to the onset of the target behavior. Each trial is recorded separately.

When to use it: Appropriate when compliance, initiation, or response speed is the clinical question. Common in ABA programs where prompt-to-response time is a teaching target, or in school psychology evaluations where transition latency or instruction-following latency is being assessed.

See Latency Recording for detailed guidance on trial timing, mean latency calculation, and response-speed assessment.

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Choosing a method

Match the method to your assessment question:

Question	Method
How often does this behavior occur?	Frequency / Event Recording
How long does this behavior last?	Duration Recording
What triggers and maintains this behavior?	ABC / Narrative Recording
Is the student generally engaged over time?	Momentary Time Sampling
Is the behavior pervasive and continuous?	Whole Interval
Does the behavior occur at all during periods?	Partial Interval
How quickly does the student respond to prompts?	Latency Recording
What is the overall classroom context?	Narrative Recording

For FBA work, ABC recording is the primary method — but it is most useful when preceded by frequency or interval data that establishes rate and identifies which sessions are worth deeper analysis.

For eligibility evaluations, interval recording (MTS or partial interval) is the most defensible choice because it produces percentage data that translates directly into discrepancy comparisons and intervention benchmarks.

When in doubt, start with MTS or partial interval. You can always add a second session with a different method once you have a clearer picture of the behavior.