How to Interpret Your MatCalc Assessment

PHV Status Section

The PHV (Peak Height Velocity) Status section tells parents where a child is on their growth journey. It indicates whether they are:

• Pre-PHV — before the major growth spurt
• Approaching PHV — nearing rapid growth
• In PHV — during the fastest growth phase
• Post-PHV — after growth has stabilised

This context helps guide expectations. For example, a child in PHV may temporarily experience coordination challenges or fatigue, which is completely normal. Understanding this prevents unnecessary worry and helps parents communicate effectively with coaches.

The Rate Graph

The Rate Graph shows whether a child's growth rate is accelerating, stable, or slowing. This visual representation makes it easy to spot trends over time.

What to look for:

• Upward trend — growth is accelerating, possibly approaching PHV
• Plateau or peak — likely at or near PHV
• Downward trend — growth is slowing as maturity approaches

This section helps explain what may be impacting coordination or fatigue levels. If the graph shows rapid acceleration, parents can understand why their child might need extra rest or seem temporarily less coordinated.

The error bands shown on the graph represent normal biological variability — small fluctuations are expected and not cause for concern.

PAH (Predicted Adult Height)

The PAH section gives insight into a child's long-term growth potential. More importantly, it shows what percentage of predicted adult height they've already reached.

Why percentage matters:

A child at 85% of PAH still has significant growth ahead, while a child at 95% is nearly at their adult height. This helps contextualize where they are developmentally compared to peers of the same chronological age.

This metric is particularly useful for:

• Understanding why teammates of the same age might have different physical capabilities
• Setting realistic expectations for strength and power development
• Explaining differences in recovery needs and injury risk

The Markers Section

The Markers section maps out key events in a child's growth timeline. It provides a longitudinal view that helps parents track changes year over year.

What markers track:

• Historical growth measurements
• Key developmental milestones (e.g., when PHV occurred)
• Significant changes in growth rate
• Timeline of maturation progress

This historical context is invaluable for seeing the bigger picture. Rather than focusing on any single moment, parents can see how their child's development has progressed over months and years.

This perspective helps maintain calm during challenging phases, knowing that growth patterns are following an expected trajectory.

Using All Sections Together

MatCalc assessments are designed to work as a cohesive whole. Each section provides different insights that, when combined, create a comprehensive picture of development.

Example interpretation:

A 13-year-old showing:

• PHV Status: "In PHV"
• Rate Graph: Peak growth velocity
• PAH: 88% of predicted height
• Recent marker: Growth rate jumped from 4cm/year to 8cm/year

What this tells you: The child is in their rapid growth phase with significant development still ahead. This is a normal time for temporary coordination challenges. Focus should be on technique, recovery, and patience rather than performance outcomes.

The key is to use this information to inform conversations and decisions, not to diagnose or prescribe. MatCalc is designed to help parents better understand what's happening — and to provide context for discussions with coaches and healthcare providers.