Introduction

The Roth Score is a simple, equipment-free bedside screening tool designed to estimate a patient's oxygen saturation (SpO2) by measuring their ability to count out loud in a single breath. The test requires no equipment beyond a timing device and can be performed in person, over the telephone, or via video consultation, making it uniquely suited for telemedicine triage, resource-limited settings, and situations where pulse oximetry is unavailable or impractical.

The test is straightforward: the patient is instructed to take a deep breath and count out loud from 1 as high as possible in a single exhalation, as quickly as they can. Two measurements are recorded: the counting number (the highest number the patient reaches before needing to take another breath) and the counting time (the total elapsed time in seconds from the start of counting to the point at which the patient stops). Both parameters correlate with pulse oximetry-measured SpO2, though the counting number has been shown to be the more reliable discriminator.

Originally described in the context of cardiac patients with dyspnea, the Roth Score gained widespread attention during the COVID-19 pandemic as clinicians sought remote assessment tools for respiratory distress in patients who could not be immediately evaluated in person. Its simplicity, zero cost, and applicability to telehealth make it a valuable adjunct in the clinical toolkit, though it is important to understand its limitations and the contexts in which it should and should not be used.

Historical Development

Origins: The Counting Test Concept

The concept of using a patient's ability to count in a single breath as a surrogate for respiratory function has roots in bedside clinical assessment that predate formal study. Experienced clinicians have long recognized that a patient who can speak in full sentences is less likely to be in severe respiratory distress than one who can only manage a few words between breaths. The Roth Score formalizes and quantifies this clinical observation into a reproducible, standardized test.

Derivation Study: Chorin et al. (2016)

The Roth Score was formally derived and characterized by Chorin and colleagues in a 2016 study published in Clinical Cardiology. The study enrolled patients presenting to a cardiology clinic or cardiac catheterization laboratory who had simultaneous pulse oximetry measurements available. Key findings from the derivation study included:

• The counting number correlated significantly with SpO2, with an area under the receiver operating characteristic curve (AUC) of 0.83 for detecting SpO2 < 95%.
• A counting number cut-off of < 15 was identified as the optimal threshold for detecting SpO2 < 95%.
• The counting time also correlated with SpO2, with a cut-off of 8 seconds yielding 78% sensitivity and 73% specificity for SpO2 < 95%.
• Both parameters were significantly lower in patients with reduced ejection fraction, active heart failure, and pulmonary congestion.

This study established the proof of concept that a simple counting maneuver could serve as a clinically useful surrogate for pulse oximetry in identifying patients with hypoxemia.

Validation Study: ten Broeke et al. (2021)

The Roth Score was subsequently validated in a primary care setting by ten Broeke and colleagues in a 2021 study published in Primary Health Care Research and Development. This validation study enrolled patients presenting to general practitioners with respiratory symptoms and provided simultaneous Roth Score testing and pulse oximetry. Key findings included:

• The counting number demonstrated a c-statistic of 0.91 for discriminating SpO2 < 95%, substantially higher than the derivation study's AUC of 0.83.
• A counting number cut-off of ≤ 20 yielded 93.3% sensitivity and 77.8% specificity for detecting SpO2 < 95%.
• A counting time cut-off of < 7 seconds yielded 85.7% sensitivity and 81.1% specificity for detecting SpO2 < 95%.
• The counting time had a notably weaker correlation with SpO2 than the counting number: the Spearman correlation coefficient for counting time was only r_s = 0.15 (P = 0.14), compared to a much stronger correlation for the counting number.
• The overall c-statistic for counting time was 0.77, compared to 0.91 for counting number, confirming that the counting number is the more reliable parameter.

COVID-19 Pandemic and Renewed Interest

The global COVID-19 pandemic (2020 onward) dramatically increased interest in the Roth Score. Several factors drove this renewed attention:

• Telemedicine expansion: The rapid shift to telehealth for initial patient assessment created an urgent need for remote screening tools that could help triage patients with respiratory symptoms without requiring an in-person visit.
• Pulse oximeter shortages: Consumer demand for home pulse oximeters during the pandemic led to supply shortages in many regions, leaving some patients without access to objective SpO2 monitoring.
• "Happy hypoxia" phenomenon: COVID-19 is characterized by silent or "happy" hypoxemia, where patients may have dangerously low oxygen levels without proportionate dyspnea. The Roth Score offered a potential screening approach for detecting this occult hypoxemia remotely.
• Resource-limited settings: In low- and middle-income countries where pulse oximeters are not universally available, the Roth Score provided a zero-cost screening alternative.

Test Administration Protocol

Standardized administration of the Roth Score is essential for reliable results. The following protocol should be followed:

Patient Preparation

1. The patient should be seated comfortably in an upright position. If the patient is unable to sit, a semi-recumbent position (head of bed elevated to 45-60 degrees) is acceptable, but this should be documented as it may affect results.
2. Allow the patient to rest for at least 2 minutes before the test to ensure baseline respiratory status rather than post-exertional measurements.
3. Explain the test clearly: "I am going to ask you to take a deep breath and then count out loud from 1 as high as you can, as fast as you can, without taking another breath. Count until you need to breathe again."
4. The patient should not be receiving supplemental oxygen during the test (if the goal is to assess room air SpO2). If the patient is on supplemental oxygen and it cannot be safely discontinued, the test should be interpreted with this context in mind.

Test Execution

1. Instruct the patient to take a single deep breath (maximum inspiration).
2. Start a timer (stopwatch, phone timer, or counting seconds) when the patient begins counting out loud.
3. The patient counts from 1 upward as quickly as possible in a single exhalation.
4. Stop the timer when the patient stops counting (either because they need to breathe or they reach 30).
5. Record two values:
   • Counting number: The highest number the patient reached (maximum 30).
   • Counting time: The total elapsed time in seconds from the start of counting to when the patient stopped.

Standardization Considerations

• Counting speed: Patients should be encouraged to count "as fast as possible" to standardize the effort. If a patient counts very slowly (deliberately pacing themselves), the counting number may be artificially reduced while the counting time may be artificially prolonged, decoupling the two measurements from their intended physiologic correlations.
• Repeat testing: If the first attempt is clearly suboptimal (e.g., the patient misunderstands the instructions, coughs during the count, or takes an additional breath), the test may be repeated after a rest period of 1-2 minutes. The best of 2-3 attempts can be used, analogous to the approach used in peak flow measurement.
• Language considerations: The test relies on counting in the patient's native language. Number systems with longer syllable counts per number (e.g., some Asian languages) may affect the counting time and potentially the counting number, though this has not been systematically studied.

Two Parameters: Counting Number and Counting Time

The Roth Score generates two complementary but distinct measurements, each with different discriminative properties:

Counting Number (Maximum Count Reached)

The counting number is the primary and more reliable parameter. It reflects the total volume of air the patient can expel while phonating and counting, which is determined by:

• Vital capacity: The total volume of air that can be exhaled after a maximum inspiration. Reduced vital capacity (from restrictive lung disease, pleural effusion, abdominal distension, neuromuscular weakness, or pain-limited inspiration) reduces the counting number.
• Airflow limitation: Obstructive airway disease (COPD, asthma exacerbation) limits expiratory airflow, reducing the rate at which air can be expelled and therefore the number of counts achievable in a single breath.
• Respiratory drive: Hypoxemia and hypercapnia increase respiratory drive, shortening the duration of voluntary breath-holding and counting. A hypoxemic patient experiences an overwhelming urge to breathe sooner than a normoxemic patient.
• Phonation efficiency: The ability to produce voice during exhalation depends on laryngeal function and the coordination of respiratory and phonatory muscles. Conditions affecting voice production (laryngeal pathology, severe weakness) may independently reduce the counting number.

Counting Time (Total Elapsed Time in Seconds)

The counting time measures how long (in seconds) the patient sustains the counting effort. While conceptually related to the counting number, it captures a partially different physiologic dimension:

• A patient who counts to 25 in 8 seconds has a different respiratory profile than one who counts to 25 in 18 seconds. The former is counting rapidly (suggesting good respiratory reserve and airflow), while the latter is counting slowly (possibly pacing themselves or having difficulty maintaining phonation).
• Counting time is more susceptible to variation in counting speed, patient effort, and comprehension of instructions, which may explain its weaker correlation with SpO2 compared to counting number.

Comparative Discriminative Performance

Parameter	c-Statistic (Validation)	Optimal Cut-off for SpO2 <95%	Sensitivity	Specificity
Counting number	0.91	≤ 20	93.3%	77.8%
Counting time	0.77	< 7 seconds	85.7%	81.1%

The counting number is clearly the superior discriminator, with a c-statistic of 0.91 versus 0.77 for counting time. When the two parameters are discordant (e.g., the counting number suggests low risk but the counting time suggests high risk, or vice versa), the more concerning (higher risk) result should take precedence, and the counting number should generally be given greater weight in clinical decision-making.

Risk Stratification and Interpretation

The Roth Score stratifies patients into three risk tiers based on each parameter independently, with the overall risk determined by the highest-risk tier reached by either parameter:

Counting Number Risk Tiers

Max Count Reached	Risk Category	Interpretation
≤ 12	High Risk	Strongly suggests SpO2 < 95%, possibly < 90%. In the derivation study, a count < 15 was optimal for detecting SpO2 < 95% (AUC 0.83). In-person evaluation with pulse oximetry is strongly recommended.
13 - 20	Intermediate	SpO2 may be < 95%. A cut-off of 20 yielded 93.3% sensitivity and 77.8% specificity for SpO2 < 95% in the validation study. In-person evaluation with pulse oximetry is recommended.
> 20	Low Risk	SpO2 likely ≥ 95%. Patients who count beyond 20 in a single breath are unlikely to be significantly hypoxemic.

Counting Time Risk Tiers

Counting Time	Risk Category	Interpretation
< 7 seconds	High Risk	Suggests possible hypoxemia. The 7-second cut-off had 85.7% sensitivity and 81.1% specificity for SpO2 < 95% in the validation study.
7 - 12 seconds	Intermediate	Borderline range. Counting time correlates weakly with SpO2 (rs = 0.15). Interpret in context with the counting number.
> 12 seconds	Low Risk	Consistent with adequate respiratory reserve. Note the lower discriminatory value of counting time versus counting number.

Overall Risk Determination

The overall risk classification is determined by the highest-risk tier reached by either parameter. For example:

• Counting number = 10 (high risk) + Counting time = 15 seconds (low risk) = Overall: High Risk
• Counting number = 25 (low risk) + Counting time = 5 seconds (high risk) = Overall: High Risk
• Counting number = 18 (intermediate) + Counting time = 10 seconds (intermediate) = Overall: Intermediate
• Counting number = 28 (low risk) + Counting time = 20 seconds (low risk) = Overall: Low Risk

This conservative approach (defaulting to the higher risk classification) ensures that patients with any concerning signal are flagged for further evaluation, consistent with the Roth Score's role as a screening tool where sensitivity takes priority over specificity.

Physiologic Basis

Understanding why the Roth Score correlates with oxygen saturation requires examining the respiratory physiology underlying the counting maneuver:

Oxygen Stores and Respiratory Drive

The ability to sustain counting in a single breath is fundamentally limited by the body's tolerance for the progressive fall in alveolar and arterial oxygen that occurs during breath-holding. During normal tidal breathing, alveolar oxygen partial pressure (PAO2) is maintained near 100 mmHg. When a patient holds their breath after a deep inspiration, PAO2 begins to fall as the fixed oxygen stores in the lungs are consumed by ongoing metabolic demand. Simultaneously, carbon dioxide accumulates in the blood, raising PaCO2.

In a patient who is already hypoxemic at baseline (SpO2 < 95%), the starting point on the oxygen-hemoglobin dissociation curve is lower, and the rate of desaturation during breath-holding is more rapid. The respiratory drive centers in the medulla (central chemoreceptors responding to CO2/pH) and carotid bodies (peripheral chemoreceptors responding to PaO2) trigger an irresistible urge to breathe sooner. The result is that the hypoxemic patient terminates counting earlier (lower counting number) and in less time (shorter counting time) than the normoxemic patient.

The Oxygen-Hemoglobin Dissociation Curve

The sigmoid shape of the oxygen-hemoglobin dissociation curve is particularly relevant to understanding the Roth Score's performance at different SpO2 thresholds:

• On the upper flat portion of the curve (SpO2 > 95%, PaO2 > 80 mmHg), small changes in PaO2 produce minimal changes in SpO2. Patients in this range have a large physiologic buffer and can sustain prolonged breath-holding (and therefore higher counting numbers).
• On the steep portion of the curve (SpO2 70-95%, PaO2 40-80 mmHg), even small decreases in PaO2 produce significant drops in SpO2. Patients on this portion of the curve desaturate rapidly during breath-holding and terminate counting much sooner.
• This explains why the Roth Score is most discriminative around the SpO2 95% threshold: patients just above this threshold are on the flat portion and can count to high numbers, while patients just below it begin to fall onto the steep portion and cannot sustain counting as long.

Respiratory Mechanics and Vital Capacity

The counting maneuver is essentially a forced vital capacity (FVC) measurement performed through phonation. Conditions that reduce vital capacity directly reduce the counting number:

• Restrictive processes: Pulmonary fibrosis, pleural effusion, pneumonia (consolidation reducing aerated lung volume), abdominal distension, morbid obesity, neuromuscular weakness (e.g., Guillain-Barré syndrome, myasthenia gravis), and chest wall deformities.
• Obstructive processes: COPD exacerbation, acute asthma, and upper airway obstruction limit expiratory flow, reducing both the counting number and time.
• Pain-limited inspiration: Rib fractures, pleurisy, post-thoracic surgery, and abdominal pain can limit inspiratory effort, reducing the starting lung volume and therefore the counting capacity.

This means the Roth Score detects not only hypoxemia per se but also conditions that impair respiratory mechanics, which themselves are often associated with or predispose to hypoxemia. This dual sensitivity (to hypoxemia and to respiratory mechanical impairment) broadens its clinical utility as a screening tool for respiratory compromise.

Voice Production and Airflow

Counting aloud requires coordinated airflow across the vocal folds, which consumes expiratory airflow more rapidly than passive exhalation. The rate of air consumption during phonation depends on vocal loudness (louder voice = greater airflow), pitch, and the acoustic characteristics of the numbers being spoken. This additional airflow demand further shortens the counting duration in patients with limited respiratory reserve, amplifying the difference between hypoxemic and normoxemic patients.

Clinical Applications

Telemedicine and Remote Triage

The most compelling contemporary application of the Roth Score is in telemedicine. During a phone or video consultation, the clinician cannot perform a physical examination, auscultate the lungs, or obtain pulse oximetry. The Roth Score provides a structured, reproducible assessment of respiratory status that can be administered remotely:

• Initial triage of respiratory complaints: A patient calling with dyspnea, cough, or chest tightness can be asked to perform the counting test as part of the remote assessment. A low-risk result (count > 20, time > 12 seconds) provides reassurance, while a high-risk result (count ≤ 12 or time < 7 seconds) prompts an in-person evaluation.
• Serial monitoring: Patients with known respiratory conditions (e.g., COVID-19 in home isolation, COPD) can perform daily Roth Score self-assessments and report results to their healthcare provider. A declining counting number over successive days may indicate clinical deterioration warranting escalation of care.
• Pandemic surge triage: During pandemic surges when ED capacity is strained, the Roth Score can help prioritize which patients need immediate in-person evaluation versus those who can be safely monitored at home with return precautions.

Resource-Limited Settings

In healthcare settings where pulse oximetry is unavailable (rural clinics in low- and middle-income countries, disaster relief settings, field hospitals), the Roth Score provides a zero-cost screening tool for hypoxemia. While it does not replace pulse oximetry, it offers meaningful clinical information in environments where no other objective assessment of oxygenation is available.

Prehospital Assessment

Emergency medical services (EMS) personnel can administer the Roth Score during initial patient contact, particularly in situations where pulse oximetry is temporarily unavailable (equipment malfunction, cold extremities preventing reliable reading, mass casualty triage). The result can supplement clinical assessment and help guide prehospital triage and transport decisions.

COVID-19 and Respiratory Illness Screening

The Roth Score gained particular prominence during the COVID-19 pandemic for several reasons:

• Silent hypoxemia detection: COVID-19 pneumonia is characterized by hypoxemia that may not produce proportionate dyspnea ("happy hypoxia"). Patients may feel relatively well despite dangerously low oxygen levels. The Roth Score provides an objective measure that can unmask this occult hypoxemia.
• Home monitoring: Patients isolating at home with confirmed or suspected COVID-19 were advised to monitor for signs of deterioration. The Roth Score supplemented subjective symptom assessment with a quantifiable parameter.
• Reducing unnecessary ED visits: By identifying low-risk patients remotely, the Roth Score helped reduce unnecessary ED presentations during periods of high healthcare system strain.

Preoperative and Perioperative Assessment

While not formally validated for this purpose, the counting test concept has potential application in preoperative assessment as a rapid bedside screening tool for respiratory reserve. A patient who cannot count beyond 10-12 in a single breath may have limited respiratory reserve that warrants further preoperative pulmonary evaluation (formal spirometry, arterial blood gas, cardiopulmonary exercise testing) before proceeding with surgery under general anesthesia.

Comparison with Pulse Oximetry

It is essential to understand the relationship between the Roth Score and pulse oximetry, and the contexts in which each is appropriate:

Feature	Roth Score	Pulse Oximetry
Equipment required	None (timer only)	Pulse oximeter device
Cost	Zero	$20-$300+ depending on device
Remote administration	Yes (phone/video)	Requires patient to have device
Continuous monitoring	No (point-in-time)	Yes
Numeric SpO2 value	No (risk category only)	Yes (continuous percentage)
Affected by skin pigmentation	No	Yes (known accuracy limitations in dark skin tones)
Affected by peripheral perfusion	No	Yes (cold extremities, shock, nail polish)
Patient cooperation required	Yes (must understand instructions and count)	Minimal (passive measurement)
Specificity for hypoxemia	Moderate (also detects respiratory mechanical impairment)	High (directly measures SaO2)
Accuracy	Screening level (c-statistic 0.91 for counting number)	Clinical standard (±2% at SpO2 70-100%)

The Roth Score is not intended to replace pulse oximetry. When pulse oximetry is available, it should always be used as the primary tool for assessing oxygen saturation. The Roth Score fills a different niche: screening for hypoxemia when pulse oximetry is not available (remote assessment, equipment failure, resource limitation) or as a complementary tool that adds physiologic information about respiratory reserve beyond what SpO2 alone provides.

Important: A "low-risk" Roth Score does not guarantee normal oxygenation. A patient with respiratory symptoms and a reassuring Roth Score should still be evaluated with pulse oximetry when it becomes available. Conversely, a "high-risk" Roth Score in a patient with confirmed normal SpO2 on pulse oximetry may indicate respiratory mechanical impairment (reduced vital capacity, airflow limitation) rather than hypoxemia, and this finding retains clinical relevance.

Strengths and Limitations

Strengths

• Zero cost and no equipment: The test requires only a timing device (phone, watch), making it accessible in any setting worldwide.
• Remote administration: Can be performed over phone or video, making it uniquely suited for telemedicine.
• Simplicity: The test can be explained to a patient in under 30 seconds and completed in under 1 minute.
• High sensitivity of counting number: At a cut-off of ≤ 20, the counting number achieves 93.3% sensitivity for SpO2 < 95%, making it a useful screening tool for ruling out significant hypoxemia.
• Strong discrimination: The c-statistic of 0.91 for the counting number approaches the performance of some more complex clinical prediction tools.
• Detects respiratory mechanical impairment: Beyond hypoxemia, the Roth Score captures reduced vital capacity and airflow limitation, providing a broader assessment of respiratory compromise.
• Not affected by skin pigmentation: Unlike pulse oximetry, which has documented accuracy limitations in patients with dark skin tones, the Roth Score is unaffected by skin color.
• Reproducible: With standardized administration, the test produces consistent results on repeated testing.

Limitations

• Screening tool only: The Roth Score does not provide a numeric SpO2 value and cannot replace pulse oximetry for clinical decision-making when oximetry is available.
• Requires patient cooperation: The patient must understand the instructions, be willing to participate, and be physically capable of speaking and counting. The test cannot be performed in patients who are:
  • Unresponsive or with severely altered mental status
  • Intubated or on non-invasive ventilation
  • Aphasic (from stroke or other neurologic conditions)
  • Severely dyspneic to the point where any phonation is impossible (paradoxically, these are the patients most likely to be hypoxemic, but they are too compromised to complete the test)
  • Very young children who cannot count
  • Patients with severe cognitive impairment who cannot follow instructions
• Counting time is a weak predictor: The validation study showed that counting time correlated poorly with SpO2 (r_s = 0.15, P = 0.14). The counting time component adds limited diagnostic value beyond the counting number alone.
• Confounding conditions: Many factors other than hypoxemia can reduce the counting number, including pain, anxiety, deconditioning, neuromuscular disease, vocal cord dysfunction, and cognitive impairment. This reduces specificity: a low Roth Score does not necessarily mean the patient is hypoxemic.
• Limited validation: While the derivation and primary validation studies show promising results, external validation across diverse populations, clinical settings, and disease states is limited. Most existing evidence comes from small, single-center studies.
• Does not detect hypercarbia: The Roth Score primarily reflects oxygen-related respiratory reserve. Patients with hypercapnic respiratory failure (e.g., COPD exacerbation with CO2 retention) may have near-normal SpO2 (especially on supplemental oxygen) but severely deranged ventilation that the Roth Score may not detect.
• Standardization challenges: Counting speed, effort, language, and accent can all affect results, and there are no universally adopted standardization protocols. This introduces measurement variability that may reduce reliability across different clinical contexts.

Special Populations and Considerations

Patients with Chronic Lung Disease

Patients with COPD, interstitial lung disease, or other chronic respiratory conditions may have chronically reduced vital capacity and airflow limitation that produces a low Roth Score even at their baseline. In these patients, the absolute Roth Score value may be less informative than the change from their personal baseline. Establishing a baseline Roth Score during a stable period and monitoring for declines may be more clinically useful than applying population-derived thresholds. A patient with severe COPD who normally counts to 15 and now can only count to 8 has experienced a meaningful decline, even though both values fall in the "high risk" or "intermediate" range.

Elderly Patients

Older adults may have reduced vital capacity, respiratory muscle strength, and phonatory endurance as part of normal aging, producing lower Roth Scores at baseline. Additionally, cognitive impairment, hearing loss, and difficulty following instructions may affect test performance. The Roth Score should be interpreted cautiously in the elderly, ideally in the context of known baseline performance and clinical correlation.

Pediatric Patients

The Roth Score has not been validated in children. Young children may not be able to count reliably, and the counting number thresholds derived from adult studies may not be applicable to the pediatric age group due to differences in lung volume, respiratory rate, and counting speed. Modified approaches (e.g., having the child sustain a vowel sound for as long as possible and measuring the duration) have been proposed but not formally validated.

Obese Patients

Morbid obesity reduces functional residual capacity, vital capacity, and expiratory reserve volume through diaphragmatic restriction and chest wall loading. Obese patients may have lower Roth Scores at baseline, particularly in the supine position. The upright seated position is especially important for testing in this population to minimize the effect of abdominal mass on diaphragmatic excursion.

Cardiac Patients

The original derivation study was conducted in cardiac patients. Heart failure with pulmonary congestion produces both hypoxemia (from ventilation-perfusion mismatch and pulmonary edema) and reduced vital capacity (from pleural effusions and pulmonary congestion), both of which reduce the Roth Score. In cardiac patients, a low Roth Score may therefore reflect both cardiac and pulmonary compromise and should prompt comprehensive evaluation.

Anxiety and Hyperventilation

Patients with anxiety, panic disorder, or hyperventilation syndrome may have difficulty performing the counting test due to an inability to sustain a controlled exhalation. Paradoxically, these patients are often normoxemic or even have elevated SpO2 (due to hyperventilation-induced respiratory alkalosis), but their Roth Score may be low due to the behavioral component of their breathing pattern. Clinical context and correlation with the patient's overall presentation are essential in these cases.

Practical Implementation Guidance

Integrating into Telemedicine Workflow

1. Identify candidates: Patients presenting with respiratory symptoms (cough, dyspnea, chest tightness, wheezing), fever with possible respiratory illness, or known cardiopulmonary disease where oxygenation assessment is clinically relevant.
2. Verify eligibility: Confirm the patient can understand instructions, count out loud, and perform the test safely (no severe respiratory distress that precludes any phonation).
3. Administer the test: Follow the standardized protocol described above. On phone consultations, the clinician times the count; on video, the clinician can both observe and time the effort.
4. Interpret results: Apply the three-tier risk stratification. Document the counting number, counting time, and risk classification.
5. Action based on result:
   • High risk: Recommend immediate in-person evaluation (ED or urgent care) with pulse oximetry and further workup.
   • Intermediate: Recommend in-person evaluation within 24 hours, or sooner if symptoms worsen. Consider home pulse oximeter if available.
   • Low risk: Continue remote monitoring with clear return precautions. Repeat the Roth Score daily if symptoms persist.

Documentation

When documenting the Roth Score in the medical record, include:

• Patient position during testing (seated, semi-recumbent)
• Whether the patient was on room air or supplemental oxygen
• Counting number achieved
• Counting time in seconds
• Risk classification for each parameter and overall
• Clinical context and any factors that may affect interpretation (chronic lung disease, anxiety, cognitive impairment)
• Clinical decision made based on the result

Combining with Other Assessment Tools

The Roth Score is most effective when used as part of a comprehensive assessment rather than in isolation. In a telemedicine context, it can be combined with:

• Respiratory rate counting: The patient or a family member can count respiratory rate over 60 seconds. Tachypnea (> 20 breaths/minute in adults) combined with a low Roth Score strengthens the concern for significant respiratory compromise.
• Symptom assessment scales: Dyspnea scales (Modified Borg, MRC dyspnea scale) provide subjective symptom quantification that complements the objective Roth Score data.
• Vital signs: Heart rate (self-palpated or from a wearable device), temperature, and blood pressure (if a home monitor is available) complete the remote vital signs assessment.
• Home pulse oximetry: When available, pulse oximetry should always be used alongside the Roth Score. Agreement between the two (e.g., low Roth Score + low SpO2) increases diagnostic confidence, while discordance (e.g., low Roth Score + normal SpO2) may suggest non-hypoxemic causes of reduced counting capacity.

Prognosis and Clinical Outcomes

The Roth Score is primarily a screening tool for point-in-time assessment rather than a prognostic instrument. However, its results carry prognostic implications in several contexts:

• Identification of deterioration: In patients with respiratory illness being monitored over time, a declining Roth Score (decreasing counting number over successive measurements) predicts clinical deterioration that may require escalation of care, even before the patient becomes subjectively more symptomatic. This is particularly relevant in conditions characterized by silent hypoxemia.
• Triage accuracy: Patients classified as high risk by the Roth Score who are subsequently found to have SpO2 < 90% on pulse oximetry represent a population with significant morbidity if not promptly treated. Early identification through remote screening enables earlier intervention, which is associated with better outcomes in conditions such as pneumonia, pulmonary embolism, and heart failure exacerbation.
• Reassurance value: Patients classified as low risk (count > 20, time > 12 seconds) can be reassured that significant hypoxemia is unlikely, reducing anxiety-driven healthcare utilization and enabling appropriate self-management with defined escalation criteria.

The long-term clinical impact of the Roth Score on patient outcomes has not been studied in randomized controlled trials. Its value is best understood as an enabling tool that facilitates timely clinical decision-making in settings where conventional assessment (including pulse oximetry) is not immediately available, rather than as a standalone diagnostic or prognostic instrument.