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TWIST score (testicular torsion)

Stratifies testicular torsion risk in boys with an acute scrotum through clinical examination, to indicate immediate surgery, Doppler ultrasound or exclusion of torsion.

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Check the population, units and version. The result shows the formula or classification; it does not make an automatic treatment decision.

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Method · Limits of application

TWIST/Barbosa 2013: 5 weighted factors, total 0–7

TWIST 2013 was initially developed in children with acute scrotum, with examination by a urologist and ultrasound in all 338 patients of the prospective cohort. Cutoffs of 2 and 5 were also assessed retrospectively; the authors still called for prospective validation. These results do not guarantee that an individual has no torsion or replace urgent assessment of a possible surgical emergency.

Conditions of use

Check the population, units, inclusion and exclusion criteria, and version in the original source. A result alone does not establish a diagnosis, discharge decision or prescription.

Documented parameters

Testicular enlargement (swelling)
Hard testicle
Absent cremasteric reflex
Nausea or vomiting
High-riding testicle

4/4 reference cases checked. Numerical tests are not clinical validation.

Sources and documentation

Documented formula

Transcribed from the source or a recorded revision; this is not a clinical recommendation.

2 points: testicular swelling; hard testis. 1 point: absent cremasteric reflex; nausea/vomiting; high-riding testis. Total 0 to 7.

References

Barbosa JA et al. Development and initial validation of a scoring system to diagnose testicular torsion in children. J Urol, 2013.

Identifier: escore-twist

Original clinical content: Brazilian Portuguese.

Method version

TWIST/Barbosa 2013: 5 weighted factors, total 0–7

escore-twist@native-2026-10-03+5a1daba0ac54

Source for the active edition

The bibliographic edition identifies the source. By itself, it proves neither full conformity of the formula nor clinical approval.

Synthetic cases checked (4)

Synthetic cases for checking the implementation, with no patient data.

Case 1

reference-001

Inputs

Nausea or vomiting: Yes
High-riding testicle: Yes
Testicular enlargement (swelling): No
Hard testicle: No
Absent cremasteric reflex: No

{
  "nausea": true,
  "alto": true,
  "edema": false,
  "duro": false,
  "cremaster": false
}

Expected result

{
  "score": 2,
  "level": "low"
}

Actual result

{
  "score": 2
}

Case 2

reference-002

Inputs

Testicular enlargement (swelling): Yes
Absent cremasteric reflex: Yes
Hard testicle: No
Nausea or vomiting: No
High-riding testicle: No

{
  "edema": true,
  "cremaster": true,
  "duro": false,
  "nausea": false,
  "alto": false
}

Expected result

{
  "score": 3,
  "level": "mid"
}

Actual result

{
  "score": 3
}

Case 3

reference-003

Inputs

Testicular enlargement (swelling): Yes
Hard testicle: Yes
Absent cremasteric reflex: Yes
Nausea or vomiting: No
High-riding testicle: No

{
  "edema": true,
  "duro": true,
  "cremaster": true,
  "nausea": false,
  "alto": false
}

Expected result

{
  "score": 5,
  "level": "high"
}

Actual result

{
  "score": 5
}

Case 4

reference-004

Inputs

Testicular enlargement (swelling): Yes
Hard testicle: Yes
Absent cremasteric reflex: Yes
Nausea or vomiting: Yes
High-riding testicle: Yes

{
  "edema": true,
  "duro": true,
  "cremaster": true,
  "nausea": true,
  "alto": true
}

Expected result

{
  "score": 7,
  "level": "high"
}

Actual result

{
  "score": 7
}

Code and reproducibility

This tool’s code on GitHub

Download code and tests

Sources, version and reproduction instructions

The code tests are technical checks. Clinical approval and professional translation review are recorded separately.

Relationship with cancer research

General context — relationship to be defined

A resource for general clinical contexts. This edition does not assign a specific oncological relationship; selecting it for a study requires a justified question, population and purpose.