Selective Mutism Test – Do I Have Selective Mutism?
Research Dataset
Selective Mutism Questionnaire (SMQ)
Normative and Psychometric Statistics
STRONG
N=421
α=0.892
49Countries
Abstract
Selective Mutism Questionnaire (SMQ)
normative dataset currently contains
421
participant records collected between
Jun 11, 2026
and
Jul 16, 2026
.
This psychometric dataset currently includes 421 anonymous participant responses collected through voluntary participation. The observed mean score was 68.71 with a standard deviation of 14.89, indicating moderate score variability within the sampled population. Internal consistency reliability analysis demonstrated good reliability (Cronbach alpha = 0.892). Observed skewness (-1.11) and kurtosis (1.69) were examined as indicators of distribution quality. The distribution demonstrated mild departures from normality, although the overall score pattern remained broadly interpretable for preliminary normative purposes.
421
Participants
49
Countries
20
Scale Items
0.892
Reliability
Table 1
Dataset Overview
Assessment
Selective Mutism Questionnaire (SMQ)
Research Status
Established Dataset
Dataset Maturity
75
/100 —
STRONG
Participants
421
Countries Represented
49
Items
20
Dimensions
5
Data Collection Period
Jun 11, 2026
–
Jul 16, 2026
Reliability
α =
0.892
Note.
The current Selective Mutism Questionnaire (SMQ) dataset contains 421 participant records collected from 49 countries. Dataset maturity reflects sample size, geographic diversity, and internal consistency reliability.
Table 2
Descriptive Statistics
Statistic
Value
Mean Score
68.71%
Median Score
71
Standard Deviation
14.89
Variance
221.69
Standard Error
0.73
95% CI Lower
67.29
95% CI Upper
70.13
Minimum Score
10%
Maximum Score
93%
Observed Range
83
Note.
M = 68.71, SD = 14.89, Median = 71. The 95% confidence interval ranged from 67.29 to 70.13.
Table 3
Sample Characteristics
Variable
Summary
Participants
N =
421
Countries
49
Age Information
Available
Gender Information
Available
Note.
Demographic information was collected voluntarily. Participant counts may vary across demographic categories when information was not reported.
Age Distribution
Age Group
Participants
under18
129
18-24
64
prefer_not
26
25-34
21
45-54
2
35-44
2
55plus
1
Gender Distribution
Gender
Participants
Female
157
Male
50
Prefer_not
38
Figure 1
Global Participation
Note.
Participants were represented across 49 countries. The largest contribution originated from US (35.9% of available geographic records).
Country
Participants
Percent
US
151
35.9%
GB
35
8.3%
DE
28
6.7%
FR
22
5.2%
NL
15
3.6%
AU
14
3.3%
BR
14
3.3%
PH
13
3.1%
CA
12
2.9%
SG
9
2.1%
NO
9
2.1%
IE
8
1.9%
SE
6
1.4%
IN
5
1.2%
FI
5
1.2%
KZ
5
1.2%
RE
5
1.2%
PL
4
1%
AT
4
1%
RU
4
1%
MD
4
1%
MX
3
0.7%
IT
3
0.7%
BY
3
0.7%
UA
3
0.7%
MY
3
0.7%
JP
2
0.5%
NP
2
0.5%
ES
2
0.5%
PK
2
0.5%
TH
2
0.5%
LT
2
0.5%
RO
2
0.5%
T1
2
0.5%
HU
2
0.5%
ID
2
0.5%
IQ
2
0.5%
MA
1
0.2%
NZ
1
0.2%
TR
1
0.2%
AZ
1
0.2%
SK
1
0.2%
DK
1
0.2%
AL
1
0.2%
AE
1
0.2%
TW
1
0.2%
GR
1
0.2%
MN
1
0.2%
CH
1
0.2%
Table 4
Percentile Norms
Percentile
Score
Interpretation
10th
50%
Very Low
25th
61%
Below Average
50th
71%
Average
75th
80%
Above Average
90th
86%
Elevated
Note.
Percentile values provide preliminary normative benchmarks derived from the current Selective Mutism Questionnaire (SMQ) sample.
Figure 2
Score Distribution
Note.
Observed scores ranged from 10% to 93% (M = 68.71, SD = 14.89). Distribution characteristics included skewness (-1.11) and kurtosis (1.69).
Distribution indices suggested mild departures from normality.
Table 5
Reliability Analysis
Metric
Value
Cronbach Alpha
0.892
Reliability Classification
Good
Participants
421
Items
20
Standard Error
0.73
Note.
Internal consistency was estimated using Cronbach alpha. Reliability estimates are based on the current normative dataset and may change as additional responses are collected.
Item–Total Correlations
Item Analysis Interpretation
Item–total correlations were generally strong across the assessment, indicating that most items contribute effectively to the measurement of the underlying construct.
The analysis identified3
itemsthat may benefit from future review.
Items Recommended for Future Review
Q1
(r = 0.03)
I am able to speak freely at home.
Q3
(r = 0.06)
I speak comfortably with close family members.
Q20
(r = -0.05)
Even when I feel safe, I sometimes struggle to speak.
The lowest item–total correlation was observed for Q20 ("Even when I feel safe, I sometimes struggle to speak."; r = -0.05), indicating comparatively weaker alignment with the overall construct.
Table 7
Dimension Norms
Dimension
Mean
SD
N
Anxiety
83.57%
18.05
421
Impairment
72.13%
22.66
421
Alternatives
71.9%
21.98
421
Consistency
58.45%
16.85
421
Speech
57.1%
18.03
421
Note.
Dimension statistics summarize normative performance across the major constructs measured by Selective Mutism Questionnaire (SMQ).
Figure 5
Dimension Profile
Note.
The highest observed dimension was Anxiety (83.6%), whereas the lowest observed dimension was Speech (57.1%). The observed difference between dimensions was 26.5 percentage points. Substantial variation was observed between dimensions.
Table 8
Dataset Growth Summary
Metric
Value
Current Participants
421
Countries
49
Collection Start
Jun 11, 2026
Collection End
Jul 16, 2026
Months Recorded
2
Note.
Growth statistics summarize cumulative participation throughout the observed data collection period.
Normative Data Notice
A total of
421
participant responses were available for this assessment.
Dimension-level norms were calculated using
421
valid response records.
Approximately
0
response record(s) were excluded from dimension-level normative calculations due to incomplete response patterns.
Limitations
Normative statistics are derived from voluntary participation and may not represent all populations. Reliability estimates, percentile norms, and dimension statistics should be interpreted in the context of the current sample and may change as additional responses are collected.
Ethical Statement
All records included in this dataset were collected anonymously. No personally identifying information is stored. Data are intended for educational, psychometric, and research purposes.
Recommended Citation
Selective Mutism Questionnaire (SMQ). Research Dataset. Retrieved from https://drdeenz.com/selective-mutism-test/statistics/