AOTG Mental Health Statistics – Fact Check
New Zealand & Australia
Movember | MEL Data Team
2026-02-16
Executive Summary
The Ahead of The Game (AOTG) team asked us to review mental health statistics used in their 2026 workshops for the New Zealand and Australian contexts
Statistics as presented in AOTG workshop materials
summary_df <- data.frame(
Statistic = c(
"2 in 5 young people experience mental illness annually",
"75% experience first symptoms by age 24",
"1 in 5 Australians have a diagnosable mental illness",
"4 in 5 NZ have experienced distress or know someone who has",
"1 in 5 Kiwis experiencing a mental health issue at any time",
"1 in 2 experience mental health issues in their lifetime"
),
Verdict = c("Update", "Supported", "Supported", "Supported", "Update", "Supported"),
Verified_Value = c("22.9%", "75%", "21.5%", "~77–80%", "13.0%", "~47%"),
Source = c(
"NZHS 2023/24",
"Kessler et al. 2005; Solmi et al. 2022",
"ABS 2020–2022",
"HPA 2020",
"NZHS 2023/24",
"HPA 2020; Te Rau Hinengaro 2003–04"
)
)
kable(summary_df,
col.names = c("Statistic", "Verdict", "Verified Value", "Source")) %>%
kable_styling(bootstrap_options = c("striped", "hover", "condensed")) %>%
column_spec(2,
background = ifelse(summary_df$Verdict == "Supported", "#27AE60",
ifelse(summary_df$Verdict == "Update", "#E67E22", "#E74C3C")),
color = "white", bold = TRUE)| Statistic | Verdict | Verified Value | Source |
|---|---|---|---|
| 2 in 5 young people experience mental illness annually | Update | 22.9% | NZHS 2023/24 |
| 75% experience first symptoms by age 24 | Supported | 75% | Kessler et al. 2005; Solmi et al. 2022 |
| 1 in 5 Australians have a diagnosable mental illness | Supported | 21.5% | ABS 2020–2022 |
| 4 in 5 NZ have experienced distress or know someone who has | Supported | ~77–80% | HPA 2020 |
| 1 in 5 Kiwis experiencing a mental health issue at any time | Update | 13.0% | NZHS 2023/24 |
| 1 in 2 experience mental health issues in their lifetime | Supported | ~47% | HPA 2020; Te Rau Hinengaro 2003–04 |
STILL ACCURATE: Three statistics are well-supported by official data sources:
- 1 in 5 Australians - ABS 2020-2022 data confirms 21.5% 12-month prevalence
- 4 in 5 New Zealanders experienced/know someone - HPA data shows 77% know someone + 31% experienced = close to 80%
- 1 in 2 lifetime prevalence - HPA reports 47% lifetime prevalence, very close to 50%
- 75% first symptoms by age 24 - Widely reported statistic in international context
NEEDS UPDATING:
- 1 in 5 Kiwis current - NZHS 2023/24 shows 13.0% high/very high distress, should be “approximately 1 in 8”
- 2 in 5 young people annual - Latest NZ data shows 22.9% for 15-24 year olds, closer to “1 in 4”
Stat 1: “2 in 5 young people” (annual prevalence)
🟧 NEEDS UPDATING
NZHS 2023/24 reports 22.9% of 15–24 year olds experienced high or very high psychological distress (K10 scale) in the past four weeks — closer to 1 in 4, not 2 in 5 (Ministry of Health, 2025).
Limitation: The NZHS measures self-reported psychological distress via the K10, not formal diagnoses. The recall period is four weeks, not 12 months, so this is not strictly annual prevalence.
Suggested revision: “Approximately 1 in 4 young people experience high levels of psychological distress.”
Stat 2: “75% experience first symptoms by age 24”
✅ SUPPORTED
The primary source is Kessler et al. (2005), the US National Comorbidity Survey Replication (NCS-R; n = 9,282), which found that half of all lifetime mental disorders have onset by age 14 and three-quarters by age 24. This finding has been corroborated by Solmi et al. (2022), a large-scale meta-analysis of 192 epidemiological studies published in Molecular Psychiatry, which confirmed that the peak and median age at onset for any mental disorder were 14.5 and 18 years respectively, with the majority of disorders emerging before the mid-20s.
Limitation: The Kessler et al. estimate is US-based and relies on retrospective recall of age of onset. The Solmi et al. meta-analysis is global but the 75% figure varies across disorder groups (e.g. higher for anxiety/neurodevelopmental disorders, lower for mood and substance use disorders).
Stat 3: “1 in 5 Australians have a diagnosable mental illness”
✅ SUPPORTED
The ABS National Study of Mental Health and Wellbeing (2020–2022) found 21.5% of Australians aged 16–85 had a 12-month mental disorder (4.3 million people). This aligns closely with “1 in 5” (Australian Bureau of Statistics, 2023).
Context: This is based on diagnostic interviews (not self-report screening), making it a strong estimate. Anxiety disorders were the most common (17.2%), followed by affective (7.5%) and substance use disorders (3.3%).
Stat 4: “4 in 5 NZ have experienced distress or know someone who has”
✅ SUPPORTED
HPA (2020) data shows 77% of New Zealanders know someone who has experienced mental distress, and 31% have experienced it themselves. These overlapping groups together support the “approximately 4 in 5” claim (Flett et al., 2020).
Limitation: The HPA data is based on the 2015–2018 Mental Health Monitor and 2018 Health and Lifestyles Survey — now several years old.
Stat 5: “1 in 5 Kiwis experiencing a mental health issue at any time”
🟧 NEEDS UPDATING
NZHS 2023/24 reports 13.0% of adults experienced high or very high psychological distress in the past four weeks — closer to 1 in 8, not 1 in 5 (Ministry of Health, 2025).
If moderate distress is included the figure rises to 32.1%, but this is a different threshold to what is typically meant by “experiencing a mental health issue.”
Context: The rate has increased substantially (from 8.3% in 2018/19 to 13.0% in 2023/24), but still falls short of 20%.
trend <- data.frame(
year = c("2013/14", "2018/19", "2023/24"),
pct = c(6.2, 8.3, 13.0)
)
ggplot(trend, aes(x = year, y = pct, group = 1)) +
geom_line(colour = "#2E86C1", linewidth = 1) +
geom_point(colour = "#2E86C1", size = 3) +
geom_text(aes(label = paste0(pct, "%")), vjust = -1, size = 3.5) +
geom_hline(yintercept = 20, linetype = "dashed", colour = "#E74C3C") +
annotate("text", x = 2.7, y = 21.5, label = "Claimed: 1 in 5 (20%)",
colour = "#E74C3C", size = 3) +
labs(x = NULL, y = "% high/very high distress",
caption = "Source: NZHS 2013/14, 2018/19, 2023/24") +
theme_minimal() +
ylim(0, 25)
NZ psychological distress over time (high/very high, K10)
Suggested revision: “Approximately 1 in 8 Kiwis are experiencing high levels of mental distress at any one time.”
Stat 6: “1 in 2 experience mental health issues in their lifetime”
✅ SUPPORTED
HPA (2020) reports 47% lifetime prevalence (Flett et al., 2020); Te Rau Hinengaro (2003–04) estimated 46.6% (Oakley-Browne et al., 2006). Both are close to “1 in 2.”
Limitation: Te Rau Hinengaro data is over 20 years old. The HPA figure draws on 2015–2018 data. No more recent NZ lifetime prevalence study exists. Australian lifetime prevalence from ABS 2020–22 is 42.9%, broadly consistent (Australian Bureau of Statistics, 2023).
Recommendations
Keep as is:
- 1 in 5 Australians have a diagnosable mental illness
- 75% of young people experience first symptoms by age 24
- 4 in 5 NZ experienced distress or know someone who has
- 1 in 2 lifetime prevalence
Update:
- “2 in 5 young people” → “1 in 4 young people experience high levels of psychological distress”
- “1 in 5 Kiwis current” → “1 in 8 Kiwis are experiencing high levels of mental distress”
Report generated 2026-02-16 | R 4.5.1