Response to Difficulty Drives Variation in IQ Test Performance.

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

Who cites it

5 citing papers in PubMed.

1. Individual Differences in Problem-Solving Behavior in Reasoning Tests: The Role of Item Difficulty and Item Position.Journal of Intelligence · 2026
   Article
2. The Role of Reinforcement Learning in Pragmatic Reasoning Tasks: Modeling and Validating the Sources of Individual Differences.Open mind : discoveries in cognitive science · 2026
   Article
3. Individual Differences in Strategy and the Item-Position Effect in Reasoning Ability Measures.Journal of Intelligence · 2025
   Article
4. Accounting for Persistence in Tests with Linear Ballistic Accumulator Models.Psychometrika · 2025
   Article
5. Log File Times as Indicators of Structured Figural Matrix Processing.Journal of Intelligence · 2025
   Article

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

Authors and funding

2 authors.

Funding

No grant is acknowledged in the PubMed record.

Abstract

Indexed as