Symmetrical vs. Asymmetrical Scales in Feedback Surveys

When designing feedback surveys, especially in healthcare, choosing the right type of scale can significantly affect the quality of the insights you gather. Symmetrical and asymmetrical scales offer distinct approaches to measuring patient experience, satisfaction, or attitudes. 

This article breaks down both types of scales, their uses, and their pros and cons.

What are symmetrical scales?

Symmetrical scales offer a balanced number of positive and negative options, typically with a neutral midpoint. This is commonly seen in Likert-type scales, where respondents might rate their experience on a 5-point scale such as:

• Very unsatisfied
• Unsatisfied
• Neutral
• Satisfied
• Very satisfied

In this example, the scale has equal weight on both the positive and negative sides, with a neutral option in the center.

Pros of symmetrical scales:

• Balance and fairness: Symmetrical scales provide an equal opportunity to express both positive and negative sentiments. This balance helps ensure that feedback represents a true distribution of opinions.
• Clear interpretation: Because the scale is balanced, it's easier to compare responses and identify trends. Neutral responses can help in determining whether respondents lean more toward the positive or negative spectrum.
• Wide applicability: Symmetrical scales are ideal for a wide range of survey types, from satisfaction to agreement and behavioral intent, allowing for versatility in question design.

Cons of symmetrical scales:

• Neutral overuse: Some respondents may default to the neutral option when unsure or unwilling to choose a definitive answer. This can skew the data toward the center and obscure useful insights.
• Limited differentiation: In cases where more nuanced feedback is needed, symmetrical scales may not offer enough differentiation between responses: e.g., a 5-point scale may not capture subtle differences in satisfaction levels.

What are asymmetrical scales?

Asymmetrical scales provide an unequal distribution of options. This means that one side of the scale may have more response options than the other, or it may entirely eliminate the neutral choice. For example:

• Excellent
• Very good
• Good
• Fair
• Poor

In this case, the scale leans more heavily toward positive responses, with only one option (Poor) to capture negative feedback.

Pros of asymmetrical scales:

• Encourages clear stance: Without a neutral option, asymmetrical scales push respondents to take a more definitive position, especially in situations where a clear response is needed.
• Targeted feedback: Asymmetrical scales are particularly useful when the goal is to push for a certain type of feedback, such as understanding if the service was "Good" or better, without focusing too much on neutrality.
• Customizable: These scales can be tailored for specific feedback types, such as post-treatment satisfaction, where you expect a majority of responses to lean positive.

Cons of asymmetrical scales:

• Potential bias: Because asymmetrical scales lack balance, they can inadvertently lead respondents toward more positive or negative responses. This skews data and may not reflect an accurate distribution of opinions.
• Difficult to analyze: Without a neutral midpoint, it's harder to assess whether a service or experience was truly negative, neutral, or positive. Respondents forced to choose between "Good" and "Fair" may not accurately represent their feelings.

Best practices for using scales in feedback surveys

Choosing the right scale for your feedback surveys will obviously be critical for gathering actionable insights. Whether you opt for symmetrical or asymmetrical scales, always make sure they align with your survey’s goals and the type of data you need. 

Following a few best practices can optimize your survey design for clarity, ease of response, and accurate data collection. Here are some key guidelines to help you implement scales in your surveys:

• Align scale type with survey objective: If the goal of your survey is to understand a full range of experiences (positive, negative, neutral), symmetrical scales are more appropriate. For more focused feedback, such as specific outcomes or performance measures, asymmetrical scales may yield clearer results.‍
• Be mindful of neutral bias: Symmetrical scales work best when you need respondents to express neutrality, but if you find many respondents overuse this option, consider removing it or using an asymmetrical scale to prompt more decisive answers.‍
• Test different scales: Before finalizing your survey, run pilot tests with both symmetrical and asymmetrical scales to see which produces the most useful data for your specific needs. Some questions may benefit from one over the other, and it’s important to find the right balance.‍
• Use asymmetrical scales sparingly: Asymmetrical scales can be powerful tools but should be used with caution. Overuse can introduce bias and distort data, especially if the goal is to gather unbiased feedback.

Conclusion

Both symmetrical and asymmetrical scales have their place in feedback surveys, especially in the healthcare industry. 

Symmetrical scales provide a balanced, neutral approach to gathering feedback, making them ideal for general satisfaction or experience-based surveys. Asymmetrical scales, on the other hand, encourage more decisive responses, making them useful for specific, outcome-oriented questions. 

If you carefully select and implement the right type of scale for your survey, you can gather more accurate and actionable insights, ultimately improving patient care and satisfaction.