24h without detected sleep in week 1.

IMPORTANT LIMITATIONS:
– N=41
– first-time mothers only
– ages 26–43
– wearable-derived sleep
– conference-supplement abstract
– should NOT be turned into a universal prediction for every parent.

2. A 2025 paternal sleep systematic review/meta-analysis included:
– 47 studies
– 17 countries
– 9, 684 fathers
– pooled sleep duration around 398 minutes (~6. 6h)
BUT heterogeneity exceeded 95% for major sleep measures.
Therefore:
do not publish “fathers get exactly 6. 6 hours” as a universal expectation.

3. A 2025 systematic review/meta-analysis of 60 postpartum studies
found sleep interventions produced a small reduction in depressive symptom severity.
It did NOT prove that improving sleep prevents postpartum depression in every person.

4. A 2024 clinical review describes postpartum sleep protection as potentially useful,
especially in higher-risk mental-health contexts.
Do not convert this into a universal prescribed number of protected hours.

5. Current evidence supports keeping:
TOTAL SLEEP
and
SLEEP CONTINUITY
separate.

SMARTSLEEPCALC RANKING DIFFERENTIATION:
1. 7-day parent-specific tracker.
2. Tracks total 24-hour sleep, including naps.
3. Tracks longest uninterrupted sleep block separately.
4. Calculates recent sleep shortfall without fragmentation multipliers.
5. Day-by-day result table.
6. First-3-days vs last-3-days continuity trend.
7. Total-sleep trend + continuity trend shown separately.
8. “Where is the problem? ” decision framework:
total sleep, continuity, opportunity, symptoms.
9. Protected Sleep Opportunity Audit.
10. Birth-parent / non-birth-parent / caregiver context without score penalties.
11. Baby age changes context only — not math.
12. No feeding-method multiplier.
13. No fake cognitive-recovery estimate.
14. No false “new parents lose X hours in year one” claim.
15. No generic “sleep when the baby sleeps” advice as the sole solution.
16. AAP-informed exhaustion/safe-feeding warning.
17. Current postpartum mental-health red flags.

MEDICAL / SAFETY CLAIM CONTROL:
– Sleep disruption after childbirth is common, but severity varies widely.
– Poor postpartum sleep is associated with mental-health symptoms,
but poor sleep does not diagnose postpartum depression.
– Sleep deprivation and postpartum depression can share symptoms.
– Postpartum psychosis is a psychiatric emergency.
– Do not attribute hallucinations, delusions, paranoia, mania or severe confusion
to “just being tired. ”
– Do not tell a severely sleepy parent they are safe to drive.
– Do not use the calculator to determine parenting fitness.
– Do not prescribe medication or supplement changes.
– Do not advise a feeding-method change purely to improve the tracker score.
– Infant feeding and lactation decisions belong with the family’s appropriate
medical/lactation professionals.
– Infant safe sleep remains separate from parent sleep calculation.

CALCULATOR METHOD:
daily shortfall = max(0, chosen target − reported total 24h sleep)
weekly shortfall = sum(daily shortfalls)
average total sleep = total reported sleep ÷ entered days
average longest block = mean of valid longest-block entries
nights/days below target = count(total sleep

#ssc-parent,
#ssc-parent *,
#ssc-parent *: :before,
#ssc-parent *: :after{
box-sizing: border-box
}

#ssc-parent{
–bg: #081412;
–bg2: #0b1d19;
–panel: #0e221d;
–panel2: #112b24;
–panel3: #15342b;
–line: #34554b;
–line2: #4a7165;
–text: #f7fbf9;
–body: #dceae6;
–muted: #b8cec7;
–soft: #92afa6;
–mint: #78e1bf;
–mint2: #bcf5e3;
–rose: #f5a9bd;
–rose2: #ffd6e1;
–blue: #a4d5ff;
–gold: #f1ca75;
–orange: #ffb17a;
–red: #ffaaa3;
–purple: #bba8ff;
–shadow: 0 18px 48px rgba(0, 0, 0, .22);
–shadow-sm: 0 8px 24px rgba(0, 0, 0, .15);

font-family: system-ui, -apple-system, BlinkMacSystemFont, “Segoe UI”, Roboto, Arial, sans-serif;
background:
radial-gradient(circle at 8% 0%, rgba(120, 225, 191, .10), transparent 30%),
radial-gradient(circle at 92% 7%, rgba(245, 169, 189, .08), transparent 29%),
linear-gradient(180deg, var(–bg), var(–bg2) 48%, var(–bg));
color: var(–body);
font-size: 16px;
line-height: 1. 7;
overflow: hidden
}

#ssc-parent a{
color: var(–blue);
text-decoration-thickness: 1px;
text-underline-offset: 3px
}

#ssc-parent a: hover{
color: #deefff
}

#ssc-parent h1,
#ssc-parent h2,
#ssc-parent h3{
margin: 0;
color: var(–text);
font-family: inherit;
letter-spacing: -. 035em
}

#ssc-parent p{
margin: 0
}

#ssc-parent button,
#ssc-parent input,
#ssc-parent select{
font: inherit
}

#ssc-parent [id]{
scroll-margin-top: 84px
}

#ssc-parent. sr-only{
position: absolute! important;
width: 1px! important;
height: 1px! important;
padding: 0! important;
margin: -1px! important;
overflow: hidden! important;
clip: rect(0, 0, 0, 0)! important;
white-space: nowrap! important;
border: 0! important
}

/* TOP TRUST BAR */

#ssc-parent. p-top{
display: flex;
justify-content: center;
align-items: center;
gap: 9px 16px;
flex-wrap: wrap;
padding: 9px 18px;
border-bottom: 1px solid rgba(255, 255, 255, .08);
background: #071612;
color: #c9ddd7;
font-size: 11. 5px
}

#ssc-parent. p-top strong{
color: #fff
}

#ssc-parent. p-pill{
display: inline-flex;
padding: 4px 9px;
border: 1px solid rgba(120, 225, 191, .18);
border-radius: 999px;
background: rgba(120, 225, 191, .08);
color: #ccf8e9;
font-weight: 750
}

/* HERO */

#ssc-parent. p-hero{
position: relative;
overflow: hidden;
padding: 72px 20px 58px;
border-bottom: 1px solid rgba(255, 255, 255, .08);
background:
radial-gradient(circle at 50% -4%, rgba(120, 225, 191, .15), transparent 34%),
radial-gradient(circle at 84% 22%, rgba(245, 169, 189, .10), transparent 28%),
linear-gradient(180deg, #081712, #0b1c18);
text-align: center
}

#ssc-parent. p-eyebrow{
display: inline-flex;
align-items: center;
gap: 7px;
margin-bottom: 16px;
padding: 7px 12px;
border: 1px solid rgba(245, 169, 189, .20);
border-radius: 999px;
background: rgba(245, 169, 189, .07);
color: #ffd5e0;
font-size: 10. 5px;
font-weight: 850;
letter-spacing: .08em;
text-transform: uppercase
}

#ssc-parent. p-hero h1{
position: relative;
z-index: 1;
max-width: 970px;
margin: 0 auto 18px;
font-size: clamp(38px, 6. 3vw, 70px);
font-weight: 880;
letter-spacing: -. 06em;
line-height: 1. 02
}

#ssc-parent. p-hero h1 em{
color: var(–rose2);
font-style: normal
}

#ssc-parent. p-lead{
position: relative;
z-index: 1;
max-width: 830px;
margin: 0 auto 22px;
color: #d4e5df;
font-size: clamp(15px, 2vw, 18px);
line-height: 1. 72
}

#ssc-parent. p-chips{
position: relative;
z-index: 1;
display: flex;
justify-content: center;
gap: 8px;
flex-wrap: wrap
}

#ssc-parent. p-chip{
padding: 7px 10px;
border: 1px solid rgba(255, 255, 255, .09);
border-radius: 999px;
background: rgba(255, 255, 255, .045);
color: #cedfd9;
font-size: 11. 5px;
font-weight: 750
}

#ssc-parent. p-author{
position: relative;
z-index: 1;
max-width: 900px;
margin: 17px auto 0;
padding: 10px 13px;
display: flex;
justify-content: center;
align-items: center;
gap: 7px 11px;
flex-wrap: wrap;
border: 1px solid var(–line);
border-radius: 13px;
background: rgba(17, 43, 36, .68);
color: #bad0c9;
font-size: 11px
}

#ssc-parent. p-author strong{
color: #fff
}

#ssc-parent. p-author a{
color: var(–mint2);
font-weight: 800
}

/* FRAME */

#ssc-parent. p-wrap{
max-width: 1120px;
margin: 0 auto;
padding: 28px 18px 70px
}

#ssc-parent. p-nav{
position: sticky;
top: 8px;
z-index: 20;
display: flex;
gap: 7px;
overflow: auto;
margin-bottom: 24px;
padding: 9px;
border: 1px solid var(–line);
border-radius: 17px;
background: rgba(8, 27, 22, .96);
box-shadow: var(–shadow-sm);
scrollbar-width: none;
-webkit-overflow-scrolling: touch
}

#ssc-parent. p-nav: :-webkit-scrollbar{
display: none
}

#ssc-parent. p-nav a{
flex: 0 0 auto;
padding: 8px 11px;
border: 1px solid #29483f;
border-radius: 999px;
background: #102820;
color: #d5e6e0;
font-size: 12px;
font-weight: 720;
text-decoration: none
}

#ssc-parent. p-card{
margin-bottom: 24px;
overflow: hidden;
border: 1px solid var(–line);
border-radius: 26px;
background: var(–panel);
box-shadow: var(–shadow-sm);
content-visibility: auto;
contain-intrinsic-size: 1px 760px
}

#ssc-parent. p-card. critical{
content-visibility: visible
}

#ssc-parent. p-inner{
padding: 30px
}

#ssc-parent. p-card h2{
margin-bottom: 10px;
font-size: clamp(25px, 3vw, 36px);
font-weight: 830;
line-height: 1. 08
}

#ssc-parent. p-card h3{
margin: 22px 0 8px;
font-size: 18px;
font-weight: 780;
line-height: 1. 25
}

#ssc-parent. p-card p,
#ssc-parent. p-card li{
color: var(–body)
}

#ssc-parent. p-card strong{
color: #fff
}

#ssc-parent. p-intro{
margin-bottom: 18px;
color: var(–muted);
font-size: 14px
}

#ssc-parent. p-kicker{
display: block;
margin-bottom: 7px;
color: var(–rose);
font-size: 10. 5px;
font-weight: 850;
letter-spacing: .1em;
text-transform: uppercase
}

/* QUICK ANSWER */

#ssc-parent. p-quick{
margin-bottom: 24px;
padding: 21px 23px;
border: 1px solid #4f615d;
border-radius: 22px;
background:
linear-gradient(135deg, rgba(245, 169, 189, .055), rgba(120, 225, 191, .05)),
#102720
}

#ssc-parent. p-quick p{
color: #e5efec;
font-size: 15px
}

/* CALCULATOR */

#ssc-parent. calc-shell{
overflow: hidden;
border: 1px solid var(–line);
border-radius: 23px;
background: #091d18
}

#ssc-parent. calc-head{
padding: 18px 21px;
border-bottom: 1px solid var(–line);
background: #0b211b
}

#ssc-parent. calc-head b{
display: block;
color: #fff;
font-size: 14px
}

#ssc-parent. calc-head span{
display: block;
margin-top: 3px;
color: #9fbab1;
font-size: 11px
}

#ssc-parent. calc-body{
padding: 22px
}

#ssc-parent. setup-grid{
display: grid;
grid-template-columns: repeat(3, 1fr);
gap: 12px;
margin-bottom: 14px
}

#ssc-parent. field{
padding: 14px;
border: 1px solid var(–line);
border-radius: 16px;
background: var(–panel2)
}

#ssc-parent. field label{
display: block;
margin-bottom: 7px;
color: #bed4cd;
font-size: 10. 5px;
font-weight: 850;
letter-spacing: .07em;
text-transform: uppercase
}

#ssc-parent. field small{
display: block;
margin-top: 6px;
color: #91ada4;
font-size: 10. 5px;
line-height: 1. 45
}

#ssc-parent input[type=number],
#ssc-parent select{
width: 100%;
min-height: 46px;
padding: 10px 11px;
border: 1px solid #52736a;
border-radius: 11px;
outline: none;
background: #091c17;
color: #fff
}

#ssc-parent. night-head{
display: grid;
grid-template-columns: 82px 1fr 1fr;
gap: 8px;
margin: 16px 0 7px;
color: #92aea5;
font-size: 9. 5px;
font-weight: 850;
letter-spacing: .07em;
text-transform: uppercase
}

#ssc-parent. night-row{
display: grid;
grid-template-columns: 82px 1fr 1fr;
gap: 8px;
align-items: center;
margin-bottom: 7px
}

#ssc-parent. night-name{
color: #c5d9d2;
font-size: 11px;
font-weight: 850
}

#ssc-parent. night-name small{
display: block;
margin-top: 2px;
color: #78958c;
font-size: 9px;
font-weight: 600
}

#ssc-parent. night-row input{
min-width: 0
}

#ssc-parent. helper-row{
display: flex;
gap: 7px;
flex-wrap: wrap;
margin-top: 11px
}

#ssc-parent. helper{
min-height: 40px;
padding: 7px 10px;
border: 1px solid #45685f;
border-radius: 10px;
background: #102821;
color: #d6e7e0;
font-size: 11px;
font-weight: 800;
cursor: pointer
}

#ssc-parent. helper: hover{
background: #17372f
}

#ssc-parent. calc-error{
margin-top: 12px;
padding: 11px 13px;
border: 1px solid #744842;
border-radius: 12px;
background: #321d1b;
color: #ffd9d5;
font-size: 12px
}

#ssc-parent. calc-error[hidden]{
display: none! important
}

#ssc-parent. calc-btn{
width: 100%;
min-height: 49px;
margin-top: 14px;
border: 0;
border-radius: 13px;
background: linear-gradient(180deg, #ffd7e1, var(–rose));
color: #37131d;
font-weight: 900;
cursor: pointer
}

#ssc-parent. calc-method{
margin-top: 12px;
padding: 12px 14px;
border: 1px solid var(–line);
border-radius: 13px;
background: #102821;
color: #b8d0c8;
font-size: 11. 5px;
line-height: 1. 6
}

/* RESULTS */

#ssc-parent. results{
margin-top: 18px;
padding-top: 18px;
border-top: 1px solid var(–line)
}

#ssc-parent. results[hidden]{
display: none! important
}

#ssc-parent. hero-result{
padding: 21px;
border: 1px solid #6c5660;
border-radius: 20px;
background:
linear-gradient(135deg, rgba(245, 169, 189, .075), rgba(120, 225, 191, .04)),
#10241f
}

#ssc-parent. result-label{
color: #e4bac6;
font-size: 10. 5px;
font-weight: 850;
letter-spacing: .08em;
text-transform: uppercase
}

#ssc-parent. result-big{
margin: 8px 0;
color: var(–rose2);
font-size: clamp(42px, 7vw, 66px);
font-weight: 900;
letter-spacing: -. 06em;
line-height: .98
}

#ssc-parent. result-summary{
color: #c8d9d4;
font-size: 13px
}

#ssc-parent. result-grid{
display: grid;
grid-template-columns: repeat(4, 1fr);
gap: 9px;
margin-top: 13px
}

#ssc-parent. metric{
padding: 12px;
border: 1px solid var(–line);
border-radius: 13px;
background: #0a1e19
}

#ssc-parent. metric b{
display: block;
color: #fff;
font-size: 17px
}

#ssc-parent. metric span{
display: block;
margin-top: 2px;
color: #98b3aa;
font-size: 10px;
line-height: 1. 4
}

#ssc-parent. continuity{
margin-top: 13px;
padding: 14px;
border: 1px solid var(–line);
border-radius: 14px;
background: #102821
}

#ssc-parent. continuity b{
display: block;
color: #fff;
font-size: 13px
}

#ssc-parent. continuity p{
margin-top: 4px;
color: #abc3bb;
font-size: 11. 5px
}

#ssc-parent. trend-grid{
display: grid;
grid-template-columns: 1fr 1fr;
gap: 9px;
margin-top: 12px
}

#ssc-parent. trend{
padding: 12px;
border: 1px solid var(–line);
border-radius: 13px;
background: #0a1e19
}

#ssc-parent. trend b{
display: block;
color: #fff;
font-size: 12px
}

#ssc-parent. trend span{
display: block;
margin-top: 3px;
color: #a9c1b9;
font-size: 10. 5px
}

/* VISUAL */

#ssc-parent. sleep-chart{
display: grid;
grid-template-columns: repeat(7, 1fr);
gap: 7px;
height: 185px;
margin-top: 16px;
padding: 14px 10px 8px;
border: 1px solid var(–line);
border-radius: 16px;
background: #091d18
}

#ssc-parent. chart-day{
height: 100%;
display: flex;
flex-direction: column;
align-items: center;
justify-content: flex-end;
gap: 4px
}

#ssc-parent. chart-track{
position: relative;
width: 100%;
max-width: 50px;
flex: 1;
overflow: hidden;
border-radius: 8px 8px 3px 3px;
background: #18342c
}

#ssc-parent. chart-total,
#ssc-parent. chart-block{
position: absolute;
left: 0;
right: 0;
bottom: 0
}

#ssc-parent. chart-total{
background: linear-gradient(180deg, var(–mint), #347965)
}

#ssc-parent. chart-block{
left: 20%;
right: 20%;
z-index: 2;
background: linear-gradient(180deg, var(–rose2), var(–rose))
}

#ssc-parent. chart-day b{
color: #fff;
font-size: 9. 5px
}

#ssc-parent. chart-day span{
color: #89a79e;
font-size: 8. 5px
}

/* COMMON */

#ssc-parent. grid2,
#ssc-parent. grid3{
display: grid;
gap: 12px
}

#ssc-parent. grid2{
grid-template-columns: repeat(2, 1fr)
}

#ssc-parent. grid3{
grid-template-columns: repeat(3, 1fr)
}

#ssc-parent. mini{
padding: 16px;
border: 1px solid var(–line);
border-radius: 17px;
background: var(–panel2)
}

#ssc-parent. mini b{
display: block;
margin-bottom: 5px;
color: #fff;
font-size: 13px
}

#ssc-parent. mini p{
color: var(–muted);
font-size: 12. 5px;
line-height: 1. 6
}

#ssc-parent. note{
margin: 16px 0;
padding: 14px 16px;
border: 1px solid var(–line);
border-radius: 16px;
background: #102821;
color: #e4f0ec;
font-size: 13px
}

#ssc-parent. note. rose{
border-color: #644952;
background: #2d2025
}

#ssc-parent. note. gold{
border-color: #65572f;
background: #2a2418
}

#ssc-parent. note. blue{
border-color: #315b76;
background: #10283a
}

#ssc-parent. note. red{
border-color: #744842;
background: #321d1b
}

#ssc-parent. formula{
margin: 15px 0;
overflow: auto;
padding: 14px 16px;
border: 1px solid rgba(120, 225, 191, .18);
border-radius: 14px;
background: #061713;
color: #dbfff3;
font: 600 12. 5px/1. 65 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace
}

/* DECISION FRAMEWORK */

#ssc-parent. steps{
display: grid;
gap: 10px;
margin-top: 17px
}

#ssc-parent. step{
display: grid;
grid-template-columns: 42px minmax(0, 1fr);
gap: 13px;
padding: 15px;
border: 1px solid var(–line);
border-radius: 15px;
background: var(–panel2)
}

#ssc-parent. step-num{
width: 42px;
height: 42px;
display: flex;
align-items: center;
justify-content: center;
border: 1px solid rgba(245, 169, 189, .28);
border-radius: 12px;
background: rgba(245, 169, 189, .08);
color: var(–rose2);
font-size: 13px;
font-weight: 900
}

#ssc-parent. step b{
display: block;
margin-bottom: 3px;
color: #fff;
font-size: 13. 5px
}

#ssc-parent. step p{
color: #b8ccc5;
font-size: 12. 5px
}

/* PLANNING */

#ssc-parent. plan-steps{
display: grid;
grid-template-columns: repeat(2, 1fr);
gap: 12px;
margin-top: 15px
}

#ssc-parent. plan{
padding: 16px;
border: 1px solid var(–line);
border-radius: 17px;
background: var(–panel2)
}

#ssc-parent. plan strong{
display: block;
margin-bottom: 5px;
color: #fff;
font-size: 13px
}

#ssc-parent. plan p{
color: #b9cec7;
font-size: 12px
}

/* TABLE */

#ssc-parent. table-wrap{
overflow: auto;
margin: 16px 0;
border: 1px solid var(–line);
border-radius: 17px;
-webkit-overflow-scrolling: touch
}

#ssc-parent table{
width: 100%;
min-width: 720px;
border-collapse: collapse;
font-size: 13px
}

#ssc-parent th{
padding: 11px 13px;
background: #132d26;
color: #cbddd7;
text-align: left;
font-size: 10. 5px;
letter-spacing: .04em;
text-transform: uppercase
}

#ssc-parent td{
padding: 11px 13px;
border-top: 1px solid #29483f;
color: #e0ece8;
vertical-align: top
}

#ssc-parent tr: nth-child(even) td{
background: #0f251f
}

/* RELATED */

#ssc-parent. related{
display: grid;
grid-template-columns: repeat(3, 1fr);
gap: 11px
}

#ssc-parent. related a{
display: block;
padding: 14px;
border: 1px solid var(–line);
border-radius: 16px;
background: var(–panel2);
text-decoration: none
}

#ssc-parent. related a: hover{
border-color: #55786e;
background: #143129
}

#ssc-parent. related b{
display: block;
margin-bottom: 3px;
color: #fff;
font-size: 13px
}

#ssc-parent. related span{
color: #b7cdc6;
font-size: 11. 5px
}

/* FAQ / SOURCES */

#ssc-parent. faq{
padding: 18px 0;
border-bottom: 1px solid var(–line)
}

#ssc-parent. faq: last-child{
border-bottom: 0
}

#ssc-parent. faq h3{
margin: 0 0 8px;
font-size: 17px
}

#ssc-parent. sources{
margin: 0;
padding-left: 20px
}

#ssc-parent. sources li{
margin-bottom: 10px;
font-size: 12. 5px
}

#ssc-parent. disclaimer{
padding: 14px 16px;
border: 1px solid var(–line);
border-radius: 14px;
background: #0a1d18;
color: #b7cdc6;
font-size: 11. 5px
}

/* ACCESSIBILITY */

#ssc-parent button,
#ssc-parent input,
#ssc-parent select,
#ssc-parent a{
transition:
background-color. 15s ease,
border-color. 15s ease,
box-shadow. 15s ease
}

#ssc-parent button: focus-visible,
#ssc-parent input: focus-visible,
#ssc-parent select: focus-visible,
#ssc-parent a: focus-visible,
#ssc-parent [tabindex]: focus-visible{
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24h without detected sleep in week 1.

Always qualify:
– small sample
– first-time mothers
– Fitbit-derived
– observational
– conference supplement

Do not write:
“all new mothers sleep 4. 4 hours. ”

9. FATHER META-ANALYSIS

Correct:
47 studies
17 countries
N=9, 684

Pooled duration:
398. 29 minutes

Very high heterogeneity:
I² > 95% on major measures.

Do not turn 6. 6h into a universal father benchmark.

10. MENTAL HEALTH

Sleep disruption may be clinically relevant.

Do NOT state:
– sleep deprivation causes all postpartum depression
– one low total predicts postpartum depression
– tracker detects depression
– parent has PPD because they cannot sleep

11. POSTPARTUM PSYCHOSIS

For someone who recently gave birth:
hallucinations
delusions
mania
paranoia
severe confusion
reality-disconnected behavior

require immediate medical attention.

Do not describe them as normal sleep deprivation.

12. U. S. EMERGENCY LANGUAGE

For U. S. audience:
988 = crisis support
911 / emergency department = immediate danger / postpartum psychosis emergency.

Do not show U. S. numbers as universal worldwide emergency contacts on localized future versions.

13. SAFE FEEDING / EXHAUSTION

AAP guidance supports warning against falling asleep with baby:
– on couch
– on soft armchair

Do not overcomplicate this section into a full infant-safe-sleep article.

Link to primary/current AAP resource.

14. FEEDING METHOD

Do not mathematically modify debt based on:
– breastfeeding
– formula
– pumping
– combo feeding

Do not imply one feeding method is superior for parent sleep.

15. LACTATION / FEEDING CHANGES

Do not tell users to:
– skip medically necessary feeds
– stop breastfeeding
– change pumping schedule
– switch to formula

solely because calculator score is poor.

16. PROTECTED SLEEP

It is acceptable to discuss creating a protected sleep opportunity when another capable caregiver can safely cover responsibilities.

Do not prescribe:
– exact universal 4h block
– exact universal 5h block

unless written as clearly attributed clinical context for a specific higher-risk population.

17. CALCULATOR FORMULA

daily shortfall =
max(0, target − total 24h sleep)

weekly shortfall =
sum(daily shortfall)

18. FRAGMENTATION

Do not:
– convert awakenings into debt
– add penalties for longest block
– multiply shortfall because block