Tool methodologies.

Each tool methodology page exists for one reason: to give curious users, researchers, and skeptics complete visibility into how a tool produces its result. We document the framework or questions being used, the exact items or variables measured, how the score is computed, any reference data (or that there is none), the known limitations, and the sources backing each claim.

The methodologies below are organized by lab. Each links to a substantive reference page written to be cited. Those that name a reviewer are independently reviewed by Eskezeia Y. Dessie, PhD.

• Brain Age Index — 2024 Lancet Commission risk factors plus brain-age-gap research: 25 self-reported inputs in six domains, weights informed by population-attributable fractions, and an estimate shown with a plus-or-minus three-year range.
• Cognitive Performance Test (Brain Vitality Index) — seven short browser tasks adapted from established paradigms (Corsi span, flanker, symbol-digit, task switching, paired associates and more), each scored 0 to 100 against provisional age ranges and combined into a Brain Vitality Age (plus or minus 4 years) and an archetype; not validated.
• Sleep-Cognition Optimizer — 12 LifeByLogic-written questions; behavioral chronotype from sleep-debt-corrected free-day midsleep (Roenneberg 2003), social jetlag, the tool’s own regularity estimate and a schedule with five scored levers.
• Sleep Need Calculator — your recommended sleep range for your age from the AASM (Watson 2015; Paruthi 2016) and National Sleep Foundation (Hirshkowitz 2015) consensus statements, and your sleep debt from the sleep you report; it does not measure sleep quality or sleep disorders.
• Cognitive Reserve Estimator — Stern’s cognitive-reserve framework (2002, 2009, 2020), up to 25 self-report items in six evidence-weighted domains and five author-chosen bands that are not percentiles; not yet validated.
• Chronotype Test — 14 LifeByLogic-written questions (the MEQ and MCTQ are cited, not administered), a 0 to 100 morningness score adjusted for age and sex, five descriptive bands and a trait-stability check; no norms yet.
• Adult ADHD Test — LBL Adult ADHD inventory v2.0: 20 LifeByLogic-written items in three domains (attention and executive function, hyperactivity-impulsivity, emotional self-regulation), 4 bands anchored to Kessler 2007 strata, 7 archetypes; not clinically validated.
• Adult Autism Self-Inventory — LBL-AAS v2.0: 30 LifeByLogic-written items on four trait patterns (social, sensory, routine, focus) plus masking and emotional-processing indices, four bands and a six-lens profile; not a validated screen.

• Cognitive Bias Susceptibility — seven bias tasks with LifeByLogic’s own questions in formats from published heuristics-and-biases experiments, every scoring formula, the Bias Blind Spot and the test’s limits; not normed or validated.
• Big Five Personality Snapshot — public-domain 30-item IPIP (Mini-IPIP plus IPIP-FFM), 5-trait OCEAN scoring, reference-value bands.
• Anxiety Test — the 7-item GAD-7 (Spitzer, Kroenke, Williams & Löwe 2006) with its standard scoring, four severity bands, published norms and validation evidence, plus a symptom profile and 5 archetypes that are LifeByLogic’s own interpretive choices.
• Future Self Continuity Index — 18 LifeByLogic-written items on how connected you feel to your future self (similarity, vividness and positivity, at 1 and 10 years), after Hershfield et al. (2011) and Sokol & Serper (2020), with a derived time-horizon stability score and 4 archetypes; not validated.
• The Inner Economy — 45 LifeByLogic-written items (39 rated statements, 6 forced-choice trade-offs) scoring 13 dimensions of how you allocate drive, attention and your appetite for risk and regard, the ten tensions between them and 9 archetypes; not validated, no norms.

• Should I Quit? — three scores from LifeByLogic’s own questions (burnout, meaning at work, intent to leave), a stay-or-go simulation with every rule and assumption listed, and its limits.
• Career Pivot Decision Matrix — six importance-weighted domains comparing your current role with the pivot (a simplified multi-attribute weighted sum; career capital after DeFillippi & Arthur 1994), four readiness items and a 5×5 recommendation grid; not validated against outcomes.

• Flourishing Index — a 25-question self-reflection test across 16 dimensions of a life (9 core, 7 context), with a composite and an archetype; its questions are LifeByLogic’s own, and it is not benchmarked against or validated by the Global Flourishing Study.
• Attachment Style Decoder — LBL-original 20-item instrument grounded in the two-factor adult attachment framework (Brennan, Clark & Shaver 1998; Mikulincer & Shaver 2007), four-archetype scoring with 4.0 cutoff rationale.
• Meaning in Life Index — 40 LifeByLogic-written items across 10 dimensions (four experience facets, six sources of meaning), six profiles and care-aware routing; builds on the MLQ (Steger et al. 2006) but is not validated or normed.
• Depression Test — the 9-item depression screener of Kroenke, Spitzer & Williams (2001), 5 severity bands, a symptom profile, item-9 crisis routing, 5 archetypes, the screener’s published validation evidence and documented author choices.
• Loneliness Test — 24 LifeByLogic-written items across four dimensions (intimate, relational and collective loneliness, plus the self-reinforcing loop), built on Hawkley, Browne & Cacioppo (2005) and Cacioppo & Hawkley (2009); not yet validated.
• Stress & Burnout Index — LBL-SBI v2.0: 24 LifeByLogic-written items in two 12-item subscales, perceived stress (after Cohen, Kamarck & Mermelstein 1983) and personal burnout (after Kristensen et al. 2005), six facets, four bands and five archetypes; no norms or validation yet.

Most methodology pages cover the following, though section names and order vary and some pages leave parts out:

• What this tool measures — the construct or constructs being assessed.
• Why it matters — the empirical case for why this measurement is worth making.
• The framework or questions used — the published instrument or model the tool uses, or a statement that its questions are LifeByLogic’s own.
• How the score is computed — the algorithm in plain math, including any reverse coding, weighting, or cutoff rules.
• Key variables and how each is measured — for each input, what it captures and how.
• Reference data and benchmarks — the populations and norming data the tool compares against, or a statement that there are none.
• Limitations — what the tool does and does not capture, including sampling limits, instrument biases, and the dimensional-vs-categorical caveats.
• Review — who reviewed the method and its scope, or a statement that no independent review is recorded.
• Version log — significant methodology changes are versioned and dated.
• Selected references — the published sources behind the page’s claims, with DOIs where the page gives them.
• Key terms — cross-links to relevant glossary entries.

Most methodology pages carry the byline of Abiot Y. Derbie, PhD, with independent analytical review by Eskezeia Y. Dessie, PhD on the pages that name a reviewer. Claims that go beyond general knowledge are sourced to published research or marked as LifeByLogic’s own choices, and the aim is that every algorithm, cutoff and benchmark a tool uses is documented in enough detail for a researcher to replicate or critique it.

For the broader editorial framework that governs how LifeByLogic content is sourced, reviewed, and corrected, see the Editorial Policy. For terms used across these methodologies, see the Glossary.