CNA Exam Preparation · Communication and Documentation

Basic Data Collection (Measurements and Vital Signs)

7 min read
Want it in plain words first? Jump to Eli explains — the same idea, no jargon.
On this page 7 sections
  1. In 30 seconds
  2. Why this matters
  3. The college version
  4. Eli explains
  5. Worked example
  6. Key takeaway
  7. Study tools

In 30 seconds

and measurements are the basic data the aide collects and reports so the nurse can spot problems early. Height and weight are measured on standing or wheelchair scales. Temperature is measured by several routes — oral, tympanic, axillary, rectal, and temporal — each with its own normal range. Normal adult pulse is 60-100 beats per minute; respirations are 12-20 breaths per minute; blood pressure has a (top) and (bottom) number. Pain is rated on a 0-10 scale or the scale. Intake and output are recorded in milliliters, where 1 ounce equals 30 mL, and urine output is measured in a graduated container.

Why this matters

Accurate data collection is the foundation of safe care — the nurse uses the aide's numbers to make decisions about medications, fluids, and when to call a provider. Small errors (the wrong route, a miscounted pulse, a missed milliliter) can lead to wrong decisions. The aide's job is to be precise, honest, and prompt in reporting, and never to guess or adjust a number to look normal. These notes are educational exam preparation only — state registry rules, NNAAP/Credentia/Prometric materials, facility policies, nurse delegation, care plans, skill checklists, and local scope-of-practice rules vary and must be followed.

The college version

1. Height, weight, and temperature

Weight changes can signal fluid gain or loss, poor nutrition, or illness. Height and weight are measured with a standing scale (the resident stands) or a wheelchair scale (the resident is weighed while seated in the wheelchair, and the wheelchair's weight is subtracted). Accuracy matters because medications and nutrition are sometimes based on weight. Report sudden weight gain (possible fluid retention) or loss (possible under-nutrition).

Temperature reflects body heat. Normal average is about 98.6°F (37°C), with a normal oral range of roughly 97.6-99.6°F. Routes include oral (mouth), tympanic (ear), axillary (armpit), rectal (rectum), and temporal (forehead). The axillary route reads about one degree lower than oral, while rectal and tympanic read about one degree higher. A fever is a sign to report. Route choice and technique follow facility policy and nurse direction.

2. Pulse, respirations, and blood pressure

Pulse is the heartbeat felt in an artery. The is felt at the wrist, and the is heard at the chest with a stethoscope. Normal adult resting pulse is 60-100 beats per minute. The aide counts for a full 60 seconds to catch irregular rhythms, and reports a rate outside the normal range or an irregular rhythm. The apical pulse is used when the rhythm is irregular or the nurse directs it.

Respirations are breaths per minute. Normal adult breathing is 12-20 breaths per minute. The aide counts respirations discreetly — without letting the resident know — because people change their breathing when they are aware it is being watched. Report an abnormal rate, rhythm, depth, or difficulty (dyspnea).

Blood pressure has two numbers: systolic (pressure when the heart contracts) over diastolic (pressure when the heart relaxes). Normal is generally below 120/80 mmHg. Report readings outside the resident's usual range, or any reading the nurse or facility defines as concerning.

3. Pain, intake, and output

Pain is the "fifth vital sign" and is subjective — only the resident knows how it feels. The 0-10 scale rates pain from 0 (no pain) to 10 (worst pain imaginable). The Wong-Baker FACES scale uses pictures of faces from smiling to crying, which is useful for children and residents who cannot use numbers. Report new or worsening pain, and its location and character as the resident describes it.

Intake is everything that goes in (fluids, foods that melt, tube feedings); output is everything that comes out (urine, emesis, diarrhea, drainage). Volumes are recorded in milliliters (mL), and 1 ounce (oz) equals 30 mL. Urine output is measured by pouring it into a graduated container (a "") and reading the level, then recording and reporting. Tracking intake and output helps detect dehydration or fluid overload.

How it works

  1. The nurse directs which measurements are needed and how often.
  2. The aide measures accurately using the appropriate equipment and route.
  3. The aide records the value in the right place on the chart or flowsheet.
  4. The aide compares the value to the resident's baseline and normal ranges.
  5. The aide reports any change or abnormal value promptly.

Common confusions

Do not confuseWithDifference
SystolicDiastolicSystolic is the top (contracting) number; diastolic is the bottom (relaxing) number
Pulse rateBlood pressurePulse is beats per minute; blood pressure is the force of blood on vessel walls
IntakeOutputIntake is fluids in; output is fluids out — both are recorded in mL
Axillary temperatureOral temperatureAxillary runs lower; do not assume the routes read the same
ozmL1 oz = 30 mL; do not confuse the two units

Memory aids

Remember "T-P-R-BP-Pain" — Temperature, Pulse, Respirations, BP (blood pressure), Pain — the vital signs as commonly charted. Add the tag "1 oz = 30 mL" for intake and output.

Quick review

Topic Recap

The aide collects and reports baseline data — height, weight, temperature, pulse, respirations, blood pressure, pain, and intake/output — so the nurse can detect changes early. Normal adult ranges are temperature about 98.6°F (route-dependent), pulse 60-100 beats per minute, respirations 12-20 per minute, and blood pressure below about 120/80. Pain is subjective and is respected as the resident reports it. Intake and output are recorded in milliliters with 1 ounce = 30 mL, and urine output is measured in a graduate. Accuracy and prompt reporting — never guessing — are the aide's responsibilities.

Knowledge Check

  1. What is the normal adult pulse range, and for how long should it be counted?
  2. How many milliliters are in 2 ounces?
  3. Why are respirations counted without the resident's awareness?
  4. Name two temperature routes and how each compares to oral.
  5. Which scale uses pictures of faces, and for whom is it useful?

Answers and Rationales

  1. 60-100 beats per minute, counted for a full 60 seconds to detect irregular rhythms.
  2. 60 mL, because 1 ounce equals 30 mL (2 x 30 = 60).
  3. People change their breathing when they know it is being watched; counting discreetly gives a natural rate.
  4. Axillary (about one degree lower than oral) and rectal or tympanic (about one degree higher than oral), among the routes; report which route was used.
  5. The Wong-Baker FACES scale, useful for residents who cannot use a 0-10 number scale, such as children or non-verbal residents.
Eli, the EliExplains learning guide

Eli explains

The same idea, in plain words

Explain it like I’m 10

Vital signs are the body's dashboard, like the gauges on a car. Temperature, pulse, respirations, blood pressure, and pain are the warning lights that tell the team how the body is running. The aide reads the gauges and reports the numbers; the nurse decides what the readings mean and what to do about them. This comparison stops being exact because a car gauge gives one fixed meaning, while a vital sign must be read in context — the same blood pressure can be normal for one person and dangerous for another. The aide reports the number and any change rather than deciding whether it is "bad."

Simple Example

A resident's temperature reads 101°F (a fever). The aide does not decide what it means or give medication. The aide records the reading accurately and reports it to the nurse, who decides what to do next.

Worked example

  1. Determine from the care plan or nurse which measurements are needed and how often.
  2. Measure accurately with the correct equipment — for a wheelchair scale, weigh the resident in the chair and subtract the chair's weight.
  3. Record the value exactly as read, in the correct place on the chart or flowsheet.
  4. Compare the value to the resident's baseline and to normal ranges (pulse 60-100, respirations 12-20, blood pressure below about 120/80).
  5. Report promptly any value outside the normal range or the resident's baseline — fever, irregular pulse, abnormal breathing, new or worsening pain, sudden weight change, or low urine output.

Key takeaways

  • High yield: Normal adult pulse is 60-100 beats per minute; normal respirations are 12-20 breaths per minute.
  • High yield: 1 ounce = 30 mL.
  • High yield: Count pulse and respirations for a full 60 seconds, and count respirations discreetly so the resident breathes naturally.
  • High yield: Pain is whatever the resident says it is — believe it and report it.
  • Normal temperature averages about 98.6°F; axillary reads lower, and rectal/tympanic read higher.
  • Normal blood pressure is below about 120/80 mmHg; report changes from the resident's baseline.
  • On a wheelchair scale, subtract the chair's weight to get an accurate body weight.
  • Sudden weight change, fever, new pain, and low urine output are all reportable.

Keep learning

Ready to build on this? Continue to the next lesson.

Study tools & related lessonsYou’ll learn to · Key vocabulary · Related

You’ll learn to

  • Explain why accurate measurement of height, weight, and vital signs matters for resident care.
  • State normal ranges for temperature, pulse, respirations, and blood pressure, and describe the routes used to measure temperature.
  • Describe pain assessment using the 0-10 scale and the Wong-Baker FACES scale.
  • Explain intake and output recording, including the 1 ounce = 30 mL conversion and the concept of measuring output in a graduate.

Key vocabulary

Vital signs
Temperature, pulse, respirations, blood pressure, pain
Systolic
The top blood-pressure number (heart contracting)
Diastolic
The bottom blood-pressure number (heart relaxing)
Radial pulse
Pulse felt at the wrist
Apical pulse
Heartbeat heard at the chest
Oral/tympanic/axillary/rectal/temporal
The temperature measurement routes
Wong-Baker FACES
A picture scale for rating pain
Intake and output (I&O)
All fluids in and out, measured in mL
Graduate
A marked container for measuring urine
mL and oz
1 ounce equals 30 milliliters

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