ACORNS: a tool for the visualisation and modelling of atypical development.
ACORNS hands you a quick sketch pad for mapping developmental sequences in kids with atypical growth.
01Research in Context
What this study did
de Graaf et al. (2011) built ACORNS, a picture language for mapping how kids with developmental delay grow. The tool turns messy milestones into clear boxes and arrows.
Instead of long reports, you get a one-page map. It shows what skill leads to what, and where the path breaks down.
What they found
The paper does not give outcome numbers. It simply shows the new symbols and how to line them up.
Authors say the maps help teams see the 'why' behind slow development, not just the 'what'.
How this fits with other research
Dowdy et al. (2022) found almost no one uses structured visual tools when they read single-case graphs. ACORNS faces the same hurdle: it exists, but analysts stick to old habits.
Manolov et al. (2023) built a free web tool that scores trend and level for you. ACORNS is hand-drawn and stays qualitative; the two tools could live on the same page—one for graphs, one for growth stories.
Toby et al. (2024) offer the POP-C calculator to pick ABA hours. ACORNS does not tell you how much therapy to order; it shows which skills to target first. Use both and you get a full plan: dosage plus roadmap.
Why it matters
Next time you assess a child with mixed delays, sketch the chain of skills in ACORNS symbols. The visual map takes five minutes and gives parents a picture they can hang on the fridge. When everyone sees the same pathway, team meetings run faster and goals feel less like jargon.
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02At a glance
03Original abstract
Across many academic disciplines visualisation and notation systems are used for modelling data and developing theory, but in child development visual models are not widely used; yet researchers and students of developmental difficulties may benefit from a visualisation and notation system which can clearly map developmental outcomes and trajectories, and convey hypothesised dynamic causal pathways. Such a system may help understanding of existing accounts and be a tool for developing new theories. We first present criteria that need to be met in order to provide fully nuanced visualisations of development, and discuss strengths and weaknesses of the visualisation system proposed by Morton. Secondly, we present a tool we have designed to give more precise accounts of development while also being accessible, intuitive and visually appealing. We have called this an Accessible Cause-Outcome Representation and Notation System (ACORNS). This system provides a framework for clear mapping and modelling of developmental sequences, illustrating more precisely how functions change over time, how factors interact with the environment, and the absolute and relative nature of causal outcomes. We provide a new template, a set of rules for the appropriate use of boxes and arrows, and a set of visually accessible indicators that can be used to show more precisely relative rates, degrees and variance of functioning over different capacities at different time points. We have designed ACORNS to give a precise and clear visualisation of how development unfolds; allowing the representation of less 'static' and more transactional models of developmental difficulties. We hope ACORNS will help students, clinicians and theoreticians across disciplines to better represent nuances of debates, and be a seed for the development of new theory.
Journal of intellectual disability research : JIDR, 2011 · doi:10.1111/j.1365-2788.2011.01471.x