SMOG Grade: A Readability Formula Explained

Overview of SMOG Grade

The SMOG (Simple Measure of Gobbledygook) Grade is a widely used readability formula. It estimates the grade level of education required to comprehend a given text. Developed by Harold C. McKinley, it’s known for its simplicity and accuracy, particularly for materials aimed at general audiences.

Key Concepts

The core of the SMOG Grade calculation involves counting polysyllabic words (words with three or more syllables) within a sample of text. The formula itself is straightforward and requires minimal computational power.

• Polysyllabic words are the primary input.
• The formula yields a grade-level score.
• It’s designed for texts of 30 sentences or more.

Deep Dive into Calculation

To calculate the SMOG Grade, you select 30 sentences from the text (10 from the beginning, 10 from the middle, and 10 from the end). Count the number of words with three or more syllables in these 30 sentences. The formula is:

SMOG Grade = 30 + (polysyllabic word count * 1.0430) - (sentence count * 30 * 0.0496)

However, a simplified version is often used: SMOG Grade = √(polysyllabic word count * 30 / sentence count) + 3. For a 30-sentence sample, this simplifies further.

Applications of SMOG Grade

The SMOG Grade is invaluable for various fields:

• Healthcare: Ensuring patient materials are understandable.
• Education: Matching texts to appropriate student levels.
• Technical Writing: Clarifying complex documentation.
• Marketing: Creating accessible content for a broad audience.

Challenges and Misconceptions

While effective, SMOG Grade has limitations. It doesn’t account for sentence structure complexity or the familiarity of terms. A common misconception is that a lower SMOG Grade always means the text is ‘dumbed down’; rather, it signifies wider accessibility.

FAQs

What is a good SMOG Grade?

For general audiences, a SMOG Grade of 8th or 9th grade is often considered ideal. This ensures the material is accessible to over 90% of adults.

Does SMOG Grade measure comprehension?

No, it estimates the educational level needed. Actual comprehension depends on reader background and text context. It’s a readability score, not a comprehension test.

Can SMOG Grade be used for very short texts?

The formula is most reliable for texts of at least 30 sentences. Shorter texts may yield less accurate results. Sample size matters.