How to Measure Social Connection
A Guide to the WHO-5, UCLA-3, and PHQ-ADS Scales
Mental health and social connection used to be things we mostly described in feelings and impressions: someone seems down, someone seems isolated, someone seems to be doing better lately. Today, there's a set of short, validated tools that let researchers and clinicians actually measure those things with some rigor, tracking change over time rather than relying on impression alone.
Here's an overview of the three most widely used tools in this space, and what the numbers behind them actually mean.
WHO-5: Overall Well-Being
The WHO-5 Well-Being Index is a five-item, self-report questionnaire developed by the World Health Organization to measure psychological well-being over the past two weeks. It asks people to rate things like how cheerful, calm, and engaged they've felt, and it produces a score from 0 to 100, where higher is better.
A score of 50 or below suggests possible depression, and scores at or below 28 approximate a clinical depression diagnosis. The commonly cited threshold for a meaningful, clinically relevant change in WHO-5 score is a 10-point increase, which gives researchers a consistent way to say whether someone's well-being genuinely shifted, rather than fluctuated within normal day-to-day variation.
UCLA-3: Loneliness
The UCLA-3 Loneliness Scale is a short, three-item version of the longer UCLA Loneliness Scale, one of the most widely validated tools in loneliness research. It asks people to rate how often they feel a lack of companionship, feel left out, and feel isolated from others. It's designed to capture the subjective, felt experience of loneliness, which is distinct from social isolation (defined as the objective absence of social contact). Someone can be surrounded by people and still score high on loneliness. Someone who lives alone by choice and stays connected through other means might not.
Because it's short and easy to administer repeatedly, the UCLA-3 is a practical tool for tracking loneliness over time, at the start of a program and at multiple points afterward, rather than just once. That repeatability is part of what makes it useful: loneliness can shift for all kinds of reasons, and a single snapshot rarely tells the full story.
PHQ-ADS: Anxiety and Depression Screener
The PHQ-ADS is a composite score combining two other well-established tools: the Patient Health Questionnaire-2, or PHQ-2, a two-item depression screener, and the Generalized Anxiety Disorder-2, or GAD-2, a two-item generalized anxiety screener. Combining them into a single score gives a broader picture of behavioral health status without requiring the longer, full-length versions of each instrument.
Tracking anxiety and depression together, rather than separately, reflects something clinicians have long observed: the two conditions are highly correlated and often show up as a pair rather than in isolation. A single combined score makes that overlap easier to see and follow over time.
Why tools like these matter
None of these instruments require a clinical setting or a lengthy evaluation to administer. A five-item or three-item questionnaire can be given at intake and repeated at regular intervals without placing much burden on the person answering it. This makes it possible to track something as personal and variable as well-being or loneliness across weeks or months, with numbers that mean the same thing from one person to the next.
That's the main idea behind all three of these scales: feelings and social connection are real, and they are measurable. We can’t always track them perfectly, but over time, we can see the meaningful patterns for an individual and know when something is actually changing.
