Explainability Factors

Demystify the elements that shape health scores with our explainability factors . At Sahha, we are dedicated to offering health analyses that are not only precise but also easy to understand. Our approach involves incorporating factors with every health score, elucidating the specific behaviors, lifestyle choices, or habits that contribute to the score's level. This enables the provision of personalized interventions and recommendations, tailored to the unique aspects of an individual’s health.

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How Do Factors Work?

At its heart, our system analyzes various inputs from an individual's daily life - like activity levels, sleep patterns, and physiological data from wearables - to calculate a health score. The factors are essentially the key elements or inputs that have the most significant influence on this score. They act as indicators, revealing which specific aspects of an individual's lifestyle or health data are contributing positively or negatively to their overall health score.

Example: Factors in Action

To facilitate a better understanding, consider this scenario: An activity score analysis where each factor—active hours, daily steps, calories burnt and so forth—contributes either positively or negatively to the final score, providing a nuanced view of what drives good or poor physical health.

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Activity-related Factors

Factor	Description	Reference
active_hours	Active Hours measures the total time a user spends being physically active during the day, defined by reaching a minimum threshold of steps.	Buckworth, Janet, and Claudio Nigg. "Physical activity, exercise, and sedentary behavior in college students." Journal of American college health 53.1 (2004): 28-34.
daily_steps	Daily Steps counts the total number of steps a user takes throughout the day. This straightforward metric is a key indicator of physical activity and is useful for setting and tracking movement goals.	Zhang, Kuan, et al. "Measurement of human daily physical activity." Obesity research 11.1 (2003): 33-40.
sedentary_periods	Captures the duration and frequency of inactivity during the day, highlighting prolonged periods with minimal to no movement. This metric highlights prolonged periods of minimal to no movement contributing to a sedentary lifestyle.	Owen, Neville, et al. "Too much sitting: the population-health science of sedentary behavior." Exercise and sport sciences reviews 38.3 (2010): 105.
activity_goals	Activity Goals assess how closely an individual's physical activity compares to the WHO recommendations for the demographic of the user. Currently this does not take in to account different workout types or heart rate. In later versions of the model this will be implemented along with the ability for ‘personalised score’ which can be set by the user.	Dunn, Andrea L., Ross E. Andersen, and John M. Jakicic. "Lifestyle physical activity interventions: History, short-and long-term effects, and recommendations." American journal of preventive medicine 15.4 (1998): 398-412.
activity_deviation	Measures the variability of steps taken during a specific hour across multiple days, providing insight into the consistency of a user’s activity level. Higher variability or sudden changes in behaviour is typically associated with unhealthy lifestyle.	Wang, Rui, et al. "StudentLife: assessing mental health, academic performance and behavioral trends of college students using smartphones." Proceedings of the 2014 ACM international joint conference on pervasive and ubiquitous computing. 2014.
calories_burnt	Estimated total active calories burnt throughout the day across different movement activities	Schwartz, Michael W., et al. "Obesity pathogenesis: an endocrine society scientific statement." Endocrine reviews 38.4 (2017): 267-296.

Sleep-related Factors

Factor	Description	Reference
total_sleep_time	Total sleep time represents the total duration of sleep a user achieves, as calculated through data from phone or wearable sensors. This metric is key for assessing overall sleep quantity, which is a key component of sleep health.	Schwartz, Michael W., et al. "Obesity pathogenesis: an endocrine society scientific statement." Endocrine reviews 38.4 (2017): 267-296.
night_time_activity	Activity recorded during usual sleep periods for the user, measured through phone usage or wearable sensors	Rajaratnam, Shantha MW, and Josephine Arendt. "Health in a 24-h society." The Lancet 358.9286 (2001): 999-1005.
sleep_regularity	Sleep regularity is consistency of the user’s bedtime and wake-up. A lower score, indicates less variation in sleep schedule over the past week, suggesting better sleep regularity, which is key for maintaining good sleep quality and overall health.	Chaput, Jean-Philippe, et al. "Sleep timing, sleep consistency, and health in adults: a systematic review." Applied Physiology, Nutrition, and Metabolism 45.10 (2020): S232-S247.
sleep_routine	Sleep routine measures the alignment of the user’s bedtime and wake time with the natural circadian rhythms of the user. It evaluates the consistency of sleep patterns in relation to the body's internal clock.	Wulff, Katharina, et al. "Sleep and circadian rhythm disruption in psychiatric and neurodegenerative disease." Nature Reviews Neuroscience 11.8 (2010): 589-599.
sleep_debt	Sleep debt is the number of cumulative hours of lost sleep over consecutive nights. The accumulation of sleep debt is not strictly linear. For example, missing 2 hours of sleep for five nights might not have the same impact as missing 10 hours in one night. Sleep debt is paid off by consistent, regular sleep timings and sleep durations.	Spiegel, Karine, Rachel Leproult, and Eve Van Cauter. "Impact of sleep debt on metabolic and endocrine function." The lancet 354.9188 (1999): 1435-1439.

Recommendations on Presenting Factors to the User

Factor	Explanation to User	Example recommendation to User
active_hours	"Active Hours represent the amount of time you spend moving enough to count as physical activity. Tracking this helps you understand how active you are and encourages you to incorporate more movement into your day.”	"Moving a little goes a long way! Regular movement throughout the day boosts heart health and reduces stress. If you've been less active, consider adding short walks or light exercises to your routine."
daily_steps	"Daily Steps show how much you've walked in a day. Keeping an eye on this number can motivate you to move more, contributing to a healthier lifestyle.”	"Every step counts! A higher step count improves cardiovascular health and aids in weight management. If you're falling short, try setting small, achievable step goals to increase your daily count."
sedentary_periods	"Sedentary Periods track how much time you spend without moving much. Reducing these periods is key to avoiding the health risks associated with a sedentary lifestyle.”	"Minimising sedentary periods can significantly enhance your health. Try to break up long periods of inactivity with short active breaks to improve your mood and reduce health risks."
activity_goals	"Activity Goals measure how your physical activity stacks up against recommended standards. It's a way to gauge if you're getting enough exercise according to general health guidelines by the World Health Organisation.”	"Meeting your activity goals is great for staying motivated and healthy. If you're finding this challenging, remember that even small increases in activity can contribute to your overall well-being."
activity_deviation	"Activity deviation tracks how much your physical activity varies at a specific hour from day to day. Consistent activity levels are generally healthier, so large fluctuations or sudden changes in your routine could indicate a need for a more regular exercise pattern.”	"Activity deviation tracks how much your physical activity varies at a specific hour from day to day. Consistent activity levels are generally healthier, so large fluctuations or sudden changes in your routine could indicate a need for a more regular exercise pattern.”
calories_burnt	"Calories Burnt shows the estimated amount of energy you've used in your activities throughout the day.”	"Burning calories through activity is essential for maintaining a healthy weight. If your activity level is low, simple activities like a brisk walk can help increase your daily calorie burn."
total_sleep_time	"Total Sleep Time is the sum of all the time you spend sleeping each night, as tracked by your phone or wearable device. It's important to know how much sleep you're getting, as it's a major factor in your overall health and well-being. Keeping track of your Total Sleep Time can help you make sure you're getting enough rest every night.”	"Adequate sleep is essential for good health and cognitive function. If you're not getting enough, try to gradually extend your sleep time to improve concentration and physical well-being."
night_time_activity	"Night Time Activity is about how much you move or use your phone during your normal sleeping hours. High activity at night, detected through your wearable device or phone, can be a sign of disrupted sleep. Keeping these activities low helps ensure you get a more restful and undisturbed night's sleep.”	"To improve your sleep quality, aim to reduce phone usage as well as physical movements in the night. If you're moving a lot at night, creating a comfortable sleep environment can help minimise disruptions."
sleep_regularity	“Sleep regularity is measured by how consistent your bedtime and wake-up times are. A lower score, indicating less variation in your sleep schedule over the past week, suggests better sleep regularity, which is key for maintaining good sleep quality and overall health.”	"A consistent sleep schedule enhances sleep quality and daily energy. If your sleep times are irregular, try to establish a more consistent routine for better overall health."
sleep_routine	"Sleep routine is about how your sleep schedule aligns with your body's natural circadian rhythms. Everyone has a unique internal clock, and finding a sleep pattern that matches this can lead to better sleep quality and more energised days. Consistency in your sleep and wake times is crucial for reinforcing a healthy sleep routine.”	"Aligning your sleep with your natural circadian rhythm improves sleep quality. If there's misalignment, consider adjusting your sleep times to be more in sync with natural light patterns."
sleep_debt	Sleep debt is the number of cumulative hours of lost sleep over consecutive nights. The accumulation of sleep debt is not strictly linear. For example, missing 2 hours of sleep for five nights might not have the same impact as missing 10 hours in one night. Sleep debt is paid off by consistent, regular sleep timings and sleep durations.	"Sleep debt can build up across multiple nights of not getting enough sleep. To catch up this debt, aim for consistent, quality rest each night to avoid the negative impacts of sleep deprivation.”

Interpreting Factor Values

Interpreting factor values correctly is crucial for understanding the health scores generated by our models. These values offer insights into how different aspects of an individual's behavior and lifestyle impact their overall health. Let's delve into some key components for interpreting these values:

Base Score

• Definition : The base_score is essentially the initial prediction of the model, calculated before considering the user's current behavior and lifestyle data. It acts as a foundational value, reflecting an individual's health status based on generalized data.
• Importance : This score serves as a starting benchmark. It allows users to understand the baseline from which the impact of each factor is measured. By comparing the final health score to the base score, users can gauge how much their current behaviors and lifestyle choices are altering their health status.

Variable Impact and Contribution

• Dynamic Influence : Each factor's influence on the health score is dynamic and changes with each analysis. This reflects the current relevance and impact of each factor on the overall health score.

• Quantifying Contribution : The contribution of each factor is quantified, showing its specific impact on the overall score. This quantification helps in understanding the degree to which a particular behavior or health metric is affecting the user's health.

Positive and Negative Values

• Dual Influence : Each factor holds the potential to influence the overall score in two ways: positively or negatively. A positive factor value signifies it contributed to increasing the score, while a negative factor value denotes it contributed to decreasing the score.

• Contextual Interpretation : In the context of wellbeing scores, like a sleep score, positive factor values are desirable. They indicate aspects of behavior or health metrics that contribute to good sleep quality or overall wellbeing. Conversely, in the context of mental health scores where a higher score might indicate more severe issues, positive values in factors can be a cause for concern, indicating behaviors or health metrics that are contributing to a higher severity of mental health issues.

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Why are Factors important?

Understanding the elements that influence health scores is crucial for two key reasons:

• Personalized Insights : Each individual's health profile is a complex interplay of various factors, including physical activity, dietary habits, sleep patterns, and stress levels. By identifying the specific factors that contribute to a person’s health score, we can provide more personalized and actionable insights. This tailored approach helps individuals understand which areas of their lifestyle have the most significant impact on their health, enabling them to make informed decisions about how to improve or maintain their well-being.
• Enhanced Motivation and Engagement : When people can see the direct correlation between their daily habits and their health scores, they are more likely to feel motivated and engaged in their health journey. This enhanced engagement is vital for fostering long-term, sustainable changes in behavior. By providing clarity on how different aspects of their lifestyle affect their health, we empower individuals to take charge of their well-being with confidence and purpose.

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Frequently Asked Questions (FAQs)

Q: What are 'Factors' in the context of health scores?
A: 'Factors' refer to the key elements or inputs, like physical activity, sleep patterns, and physiological data from wearables, that significantly influence an individual's health score. They help in understanding how specific behaviors and lifestyle choices impact overall health and well-being.

Q: How is the base_score different from the final health score?
A: The base_score is the initial prediction of our models, calculated before considering the user's current behavior and lifestyle data. It acts as a foundational benchmark. The final health score, on the other hand, incorporates the impact of the factors, reflecting the influence of current behaviors and lifestyle choices on the user's health.

Q: Why does the influence of each factor change over time?
A: The influence of each factor is dynamic because it reflects the current relevance and impact of that factor on the overall health score. As a person's lifestyle and health data evolve, the significance of each factor also changes, ensuring the health score remains accurate and relevant.

Q: How can users leverage the information provided by factors?
A: Users can use the insights from factors to understand which areas of their lifestyle are most significantly impacting their health. This information can guide them to make informed decisions about their health, set realistic goals, and undertake actionable steps towards improving or maintaining their well-being.

Q: Are these factors universally applicable to all individuals?
A: While the factors are based on general health principles, their impact is personalized. This means that the same factor can have different levels of influence for different individuals, depending on their unique health profiles and lifestyles.