What is the Katz 15 Scale?
Also known as the Modified Katz ADL scale, the Katz 15 scale is a comprehensive tool used by healthcare professionals to assess the functional independence of older adults. It integrates elements from the original Katz-6 scale (basic ADLs) and the Lawton IADL scale (instrumental ADLs) for a more complete picture necessary for independent living.
The Development of the Katz 15 Scale
The Katz 15 scale builds upon earlier functional assessment tools like the original Katz Index of Independence in Activities of Daily Living (Katz-6), which focused on six basic self-care tasks. The Lawton IADL scale evaluated more complex tasks needed for community living. The combination resulted in the Katz 15.
Components Assessed by the Katz 15 Scale
The Katz 15 scale evaluates 15 items, categorized into basic and instrumental activities of daily living, plus two additional items.
Basic Activities of Daily Living (ADLs)
These fundamental self-care tasks include bathing, dressing, toileting, transferring, continence, and feeding.
Instrumental Activities of Daily Living (IADLs)
These more complex tasks include telephoning, shopping, preparing meals, housekeeping, traveling, medication management, and finances.
Additional Items
Two further items are personal hygiene and walking about.
Scoring and Interpretation
The Katz 15 is typically scored by assigning points for independence in each task, resulting in a score from 0 to 15, with a higher score indicating greater independence. This provides a broader assessment range compared to the Katz-6.
Purpose and Advantages
The primary goal of the Katz 15 is to assess functional status and predict future health outcomes. It offers enhanced predictive validity for unfavorable outcomes like hospitalization and is useful for personalizing care plans and monitoring changes.
Comparison: Katz 15 vs. Katz 6
| Feature | Katz 15 Scale | Katz 6 Scale |
|---|---|---|
| Scope | Comprehensive, including both Basic ADLs and Instrumental ADLs. | Limited to only Basic ADLs. |
| Number of Items | 15 items. | 6 items. |
| Sensitivity | High, capable of detecting a wider range of functional abilities and subtle changes. | Lower, less sensitive to incremental changes, especially in highly dependent individuals. |
| Floor Effect | Reduced, better for assessing individuals with lower functional status. | Present, can show poor discrimination among people with low functioning. |
| Predictive Power | Stronger predictor of unfavorable health outcomes like hospitalization or institutionalization. | Weaker predictor, as it lacks the IADL components that correlate with long-term prognosis. |
| Application | Suitable for broader screening and detailed care planning. | Useful for quick, basic functional screening, especially in early stages of assessment. |
Limitations and Considerations
The Katz 15 scale does not measure cognitive function, and cultural factors may not be fully captured. It is best used as part of a comprehensive geriatric assessment alongside other tools. For more resources, visit {Link: Hartford Institute for Geriatric Nursing website https://hign.org/consultgeri/try-this-series/katz-index-independence-activities-daily-living-adl}.
Conclusion
The Katz 15 scale provides a valuable assessment by integrating both basic and instrumental activities of daily living. Its ability to predict health outcomes and offer a detailed view of capabilities makes it a crucial tool in geriatric care for developing personalized care plans.
