FAQ

The app measures the Angle of Trunk Rotation, or ATR, using your phone’s motion sensors. You lay the phone across the back during the forward bend test and it reads the difference in height between one side of the trunk and the other, in degrees.

This is the same quantity the school screening measures. It is a screening measurement, not a diagnosis, and it is not the curve measured on an X-ray.

Yes. Health Promotion Board screeners use a scoliometer and record an Angle of Trunk Rotation, not a Cobb angle. The app performs the same measurement with the phone’s sensors instead of a mechanical instrument.

That means a reading you take at home is directly comparable to the kind of number recorded at school, provided your technique is consistent.

Scoliosis screening has been part of the annual school health screening since 1982, in all primary and secondary schools. The scoliosis check is carried out for girls in Primary 5 and Primary 6.

Screening is done by female doctors or nurses in private enclosed cubicles. Arrangements can change, so confirm the current position with your child’s school or HealthHub.

Boys are not part of the Primary 5 and Primary 6 scoliosis check, so nobody at school is looking. Scoliosis is less common in boys, but it happens, and it is sometimes found later precisely because no one was checking.

If your son has a visible asymmetry, a rib hump when he bends forward, or uneven shoulders, measure at home and take the reading to a doctor.

Singapore refers at an ATR of 5° or more. That is lower than the 7° threshold used by many screening programmes elsewhere, and it means Singapore casts a deliberately wider net.

On this page we follow Singapore practice. If your child’s reading is 5° or above, that is the local referral point, whatever a general international guide may say.

Children who screen positive are referred to a Student Health Centre for a second, more detailed screening. If the raised reading holds there, a PA radiograph is taken so a Cobb angle can be measured properly.

The school screening itself does not diagnose scoliosis. It identifies the children worth examining more closely.

A study of 93,626 students screened through the national programme found prevalence in girls rising sharply with age: 0.27% at 9, 0.64% at 10, 1.58% at 11, 2.22% at 12, and 2.49% at 13.

That pattern is the reason screening sits at Primary 5 and Primary 6 and the reason the growth spurt is the period to watch. Source: Yong F, Wong HK, Chow KY, Annals of the Academy of Medicine Singapore, 2009, PubMed PMID 20052440.

School screening happens once a year. Curves progress fastest during the growth spurt, and a year is long enough for a curve to move considerably between checks.

A reading every few months fills that gap and gives you a dated series rather than two isolated numbers. It also means a change is noticed by you rather than waiting for the next round.

No. The Cobb angle comes from a radiograph and can only be measured on an X-ray. The app measures rotation at the surface of the back.

The two are related but not interchangeable, and an ATR reading cannot be converted into a Cobb angle. See ATR and the Cobb angle compared.

No, and neither does the school screening. Both do the same job: they identify children whose trunk is rotated enough to deserve a closer look.

The diagnosis is made later, by a clinician, with an examination and where necessary a radiograph. Treat a raised number as the reason to start that process rather than as its conclusion.

Ask your child to stand with the feet together and the knees straight, then fold forward from the hips, arms hanging and palms together, until the upper back is roughly parallel with the floor. Crouch down so you are looking along the back rather than down on it.

Rest the phone across the back at right angles to the spine, start high and work down, and keep the largest figure. Photographs and the usual mistakes are in our forward bend test guide.

Small readings are common and a perfectly symmetrical back is unusual. Under 5° is generally treated as within normal variation, and 5° is also Singapore’s referral point, so that figure matters here in two ways.

Stability over time matters as much as any single number. More detail is in our guide to normal scoliometer readings.

Screening research reports that an ATR near 5° corresponds on average to a Cobb angle near 11°, and an ATR near 7° to a Cobb angle near 20°. These are group averages and an individual can sit well above or below them.

A reading cannot be converted into a Cobb angle. What 5, 7 and 10 degree readings mean sets out the thresholds.

If your child was referred through school, follow that referral. Otherwise start with a polyclinic or your family doctor, who can examine your child and refer on to a paediatric orthopaedic or spine service.

Going through the referral route rather than presenting directly at a specialist clinic also affects the subsidy you are eligible for, so it is worth doing in order. More in when to see a specialist.

Your dated readings — date, which part of the back, the number, and who took the measurement. Bring the school screening result too, if you have it.

A doctor seeing your child once cannot tell whether a curve is changing. A record over several months answers a question the appointment itself cannot.

Once a quarter suits most growing children with no diagnosed curve, and it fits neatly around the annual school check rather than duplicating it. If a specialist is already following a curve, use the interval they have given you.

Weekly measurement adds nothing. A curve that is going to change does so across months, so more frequent readings mostly capture the unsteadiness of your own hand.

Ideally the same person every time. The instrument is consistent; the operator is where the variation creeps in — how deep the bend is, exactly where the phone lands, how firmly it is held.

One measurer, one place in the house, and a series worth comparing. Alternate between two adults and you will find yourself unable to tell a real change from a change of hands.

Yes, and it is the commonest reason a home figure disagrees with a clinic one. The sensors report how the phone is tilted, so a case with a proud camera housing or a raised rim holds the phone off the skin at an angle and quietly adds that angle to every reading.

Take the case off if you can, or commit to using the same one throughout. Avoid pressing hard as well, since compressing the tissue on the raised side reduces the difference you are trying to measure.

The trend is the signal. An increase in the region of 5° from one session to the next deserves a professional opinion, even where the figure on its own seems unremarkable.

Repeat it first, and confirm nothing about your technique has changed, because method drift alone can account for several degrees. If the rise holds up, take it to a doctor. Curves can progress without pain and without a change anyone would notice by eye.

Yes. Adults typically use it either to follow a curve identified in childhood or to attach a figure to an asymmetry they have noticed alongside back pain.

The timescale is different. Adult curves move slowly, so measure at longer intervals and do not read much into small fluctuations. Anything new, or anything changing quickly, warrants a doctor rather than a home log.

Not on our side. The Data safety declaration on the app’s Google Play listing states that no user data is collected and none is shared with third parties; readings live on your own handset.

That also means we cannot recover them if the phone is lost or replaced. Keep a parallel note — date, region of the back, figure, and who took it — and bring that to the polyclinic or clinic with you.

Whichever store processed the payment handles the refund. Subscriptions taken out inside the app are billed by Apple or Google, and only they can reverse the charge.

Contact Apple or Google support through the account used for the purchase. We have no access to store billing and cannot issue a refund on their behalf.

Yes, without paying again. Sign in with the Apple ID or Google account that made the original purchase and both the app and your entitlement are restored.