Myopia control trials follow children for two to three years and measure small changes in refraction and axial length in each eye. Capture keeps per-eye measurements, parent diaries and assent in one study. Test free, pay only at go-live.
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| Assessment | Screen | Baseline | M6 | M12 | M24 | M36 |
|---|---|---|---|---|---|---|
| Cycloplegic autorefraction (each eye) | ||||||
| Axial length biometry (each eye) | ||||||
| Visual acuity and slit lamp | ||||||
| Parent diary: drops, outdoor time | D | D | D | D | D | |
| Photophobia and near-vision questions | ||||||
| Adverse events |
x = visit form, D = caregiver diary entries
What a myopia control trial needs from its EDC
The study data
The effects measured in myopia control are small. A pooled analysis of placebo-controlled 0.01% atropine trials reported differences in the order of 0.14 dioptre per year in spherical equivalent and 0.05 mm per year in axial length, with considerable variation between trials. With margins that small, one transcription slip or a missing eye matters. Capture lets each eye be a separate set of typed fields with range checks, and a calculated mean of both eyes appears read-only for the reviewer.
Registered protocols differ on what is primary. The UK low-dose atropine trial lists cycloplegic autorefraction spherical equivalent at two years, adjusted for baseline. A Danish registration lists axial length elongation and spherical equivalent change at 36 months as primary endpoints. Build the endpoints you were given, and put the measurement conditions into fields: cycloplegic agent, time after instillation, instrument, and operator. Different instruments and different cycloplegic timing are the common hidden sources of noise, and they can be queried when they are blank.
Axial length is a device output, usually an optical biometer reading repeated several times per eye. A table section on the form can hold the repeated readings with a calculated mean and an edit check on spread you define. Capture does not connect to biometers or autorefractors; staff enter or paste values, and each entry sits under their name in the audit trail. SDV can be set per field if monitors need to check the primary measures against the source printout.
Right eye
Cycloplegic spherical equivalent
SE_RAxial length, mean of readings
AL_RFrom the repeated readings table
24.31 mm CalculatedLeft eye
Cycloplegic spherical equivalent
SE_LAxial length, mean of readings
AL_LChange since baseline above the range set for this study
Minutes since cycloplegic drops
CYCLOTProtocol to build
| Protocol element | What the data looks like | Where it lives in Capture |
|---|---|---|
| Cycloplegic refraction | Sphere, cylinder, axis per eye; calculated spherical equivalent | Site eCRF form per eye with range checks |
| Axial length | Repeated readings per eye, mean | Table section of repeating rows, calculated mean |
| Visual acuity and anterior segment | Best-corrected acuity, slit lamp, intraocular pressure | Site form per visit |
| Compliance | Drop count or lens wear hours, missed doses | Parent diary on a phone, or a site form at visits |
| Outdoor time and near work | Weekly hours, screen time | Parent questionnaire; see parent proxy ePRO |
| Tolerability | Photophobia, near-blur, glare, discomfort | Short participant questionnaire plus adverse event form |
| Parent permission and assent | Signed, countersigned, per age band | Paediatric assent template in eConsent |
| Treatment arms | Dose strengths, lenses, placebo, wash-out | Arms and epochs, with blinded roles masked |
Capture does not supply instrument wording or verify licences. Dioptre and millimetre ranges in checks are yours to set from the protocol.
Create per-eye fields, the axial length table and the parent diary, then enter sample children. Free sandbox, no credit card.
Children and families
Participants are usually six to twelve years old, so every study needs parent or guardian permission and child assent suited to age. Capture eConsent supports participant and countersignature flows, an optional witness and Legally Authorized Representative signature, and a paediatric assent template to start from. Your ethics committee sets wording and age bands. See eConsent software for clinical trials and EDC for paediatric clinical trials.
Retention over two to three years is the operational risk. Annual visits with six-monthly checks lose families to moves and lost interest, and children who drop out are often those whose myopia progressed fastest. A visit window around each month and dashboards of overdue visits per site help staff call families before the window closes. Reminders go by email or SMS, and the parent diary gives a light-touch contact between visits.
Digital and optical designs, such as multifocal lenses, ortho-k, or red-light therapy, move the weight to wear-time, device use and tolerability. The EDC fields change, the data model does not. If your device logs usage, plan how that file will be reconciled with the diary. Capture does not integrate with devices beyond its native wearable sync; see EDC for wearable device studies.
Before first participant
Cycloplegic agent, timing, instrument and operator fields on the form.
Both-eye mean or study eye chosen and documented in the SAP.
Parent permission and child assent per age band.
Visit windows, overdue dashboard and reminder rules.
Plausible refraction and axial length ranges and change thresholds.
If used, with its own visits and blinded roles.
Yes. Right and left eye are separate typed fields or form sections, with a calculated mean shown read-only. Which eye is analysed is a decision for your SAP.
No. Values are entered or pasted by staff, each under a named user in the audit trail. Capture does not claim device integrations other than native wearable sync.
Yes. An assessment can be completed by a caregiver, opened from a secure link on their phone, with reminders and a completion window you set.
Through eConsent, with a paediatric assent template to start from and countersignature. Ethics committees decide the wording and age bands.
Yes. Capture suits Phase 1, 2 and 3, with multi-site numbering, a coordinator portal and by-site exports.
The sandbox is free with every feature. You pay once real participants enter; see the pricing page for plans.
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