Pain is the only vital sign without a universal objective measure — and for patients who can't speak for themselves, that gap can mean real suffering goes unrecognized. Premature infants, children with autism or intellectual disabilities, adolescents with chronic pain, and dementia patients all face a common problem: their pain signals don't come in words. Instead, they show up as a furrowed brow, a refusal to walk, a sleepless night, or unexpected irritability — cues that are easy to miss or misattribute.

The stakes are high. Repeated painful procedures in neonatal ICUs without adequate pain management can affect neurological development. In dementia patients, an estimated 40–80% experience regular pain, yet it's frequently attributed to disease progression rather than a treatable cause. And for adolescents with chronic pain, being disbelieved can be just as disabling as the pain itself.

By the Numbers

• 66.7% of Spanish NICUs did not systematically use a clinical pain scale
• Only 16.7% of newborns were assessed even once with a validated scale during hospitalization
• Premature infants may undergo a median of 16 painful procedures per day
• 40–80% of dementia patients experience pain regularly, yet it remains underdiagnosed
• A 2025 systematic review of 25 studies found AI tools show promise for pain detection in non-communicative patients

Why it matters: Technology — from pupil-tracking devices like the Nociometer to AI-powered facial expression analysis — is advancing fast. But a 2025 review in BMC Anesthesiology found the biggest obstacles aren't technological: they're lack of training, poor protocol implementation, and limited clinical time. Better tools matter, but so does having the time to actually use them.