How Can We Improve Estimates of Depression Prevalence in Chile?

What you need to know

• Combining data from Chile’s national health survey with records from a depression treatment program provides a more accurate estimate of depression prevalence.
• The combined data shows depression prevalence is 6.65%, higher than the 6.19% estimated by the survey alone.
• This translates to over 63,000 additional cases of depression not captured by the survey data alone.
• More accurate prevalence estimates can help improve budgeting and policies for depression prevention and treatment.

Improving Depression Prevalence Estimates

Major depressive disorder (MDD) is a significant public health issue in Chile and around the world. Understanding how common depression is in the population is crucial for proper planning and allocation of mental health resources. However, getting accurate estimates of depression prevalence can be challenging.

This study aimed to improve estimates of depression prevalence in Chile by combining two data sources: the Chilean National Health Survey and records from a national depression treatment program. The researchers found that this combined approach provides a more comprehensive picture of depression in Chile compared to survey data alone.

Why Accurate Prevalence Estimates Matter

Depression prevalence refers to the percentage of people in a population who have depression at a given time. Accurate prevalence estimates are important for several reasons:

• They help health officials understand the true scope of depression in the population
• This information guides decisions about funding and resources for mental health services
• Tracking prevalence over time shows whether depression rates are increasing or decreasing
• Comparing prevalence across regions can reveal disparities in mental health

Underestimating depression prevalence could mean that mental health needs are not being fully met. On the other hand, overestimates could lead to misallocation of limited healthcare resources. Getting the most accurate picture possible is key.

Challenges in Measuring Depression Prevalence

Measuring depression prevalence is not straightforward. Common approaches like population surveys have limitations:

• People may be reluctant to report depression symptoms due to stigma
• Survey questions may not perfectly capture clinical depression
• Surveys usually only reach a small sample of the total population
• People with depression may be less likely to participate in surveys

Clinical records can provide additional data, but also have drawbacks:

• Not everyone with depression seeks treatment
• Diagnoses may be inconsistent across providers
• Records may be incomplete or inaccessible

Given these challenges, combining multiple data sources can help provide a more complete picture.

The Chilean Context

Chile has made efforts to improve depression care in recent years. In 2001, the country implemented a National Depression Detection, Diagnosis and Treatment Program in primary care. In 2005, depression treatment was added to Chile’s national health plan, guaranteeing access to care.

However, utilization of the depression treatment program has been lower than expected based on previous prevalence estimates. This raises questions about whether depression prevalence may be lower than thought, or if there are barriers preventing people from accessing care.

A New Approach to Estimating Prevalence

To get a more accurate estimate of depression prevalence, this study combined two key data sources:

1. The 2016-2017 Chilean National Health Survey (ENS)
2. Records from Chile’s Explicit Health Guarantees (GES) program for depression treatment

The National Health Survey used diagnostic interviews to estimate depression prevalence in a sample of the population. The GES program records provide data on people diagnosed with depression who accessed treatment.

By combining these sources, the researchers aimed to capture both diagnosed cases and cases in the general population that may not have sought treatment.

What the Study Found

When looking at the National Health Survey data alone, the estimated prevalence of major depression in adults 18 and older was 6.19%.

After combining the survey data with the GES program records, the estimated prevalence increased to 6.65%.

This 0.46% increase may seem small, but it translates to over 63,000 additional cases of depression at the population level.

Some key findings by region:

• The Southern zone showed the largest increase in prevalence with the combined approach, rising by 0.7%
• In the Metropolitan region, which includes Santiago, prevalence increased by 0.55% - accounting for over 30,000 additional cases

Why the Combined Estimate Matters

The higher prevalence estimate from the combined data approach is important for several reasons:

1. It suggests previous estimates based on survey data alone may have underestimated depression prevalence.

2. The additional 63,000+ cases represent people whose mental health needs may not have been fully accounted for in health planning.

3. More accurate regional estimates can help identify disparities and target resources appropriately.

4. Understanding the gap between survey estimates and clinical records can reveal potential barriers to care that need to be addressed.

Implications for Mental Health Policy and Planning

These findings have several implications for mental health efforts in Chile:

• Budget allocations for depression treatment may need to be reconsidered to account for the higher number of cases.

• Strategies to increase utilization of the national depression treatment program should be explored, given the gap between prevalence and program use.

• More provider training or resources may be needed in regions showing higher than expected prevalence.

• Further research is warranted to understand why some cases are not being captured in either surveys or treatment records.

Limitations to Consider

While this combined data approach improves upon survey estimates alone, there are some limitations to keep in mind:

• The GES program data may have some inaccuracies or inconsistencies in diagnoses.

• Cases of depression that do not result in treatment are still not fully captured.

• The survey data used a subsample that limits analysis to broad regions rather than more specific local areas.

• Diagnostic criteria and methods differ somewhat between the survey and clinical records.

Conclusions

• Combining national survey data with health program records provides a more comprehensive estimate of depression prevalence in Chile.
• The combined estimate suggests depression may be more common than previously thought, affecting 6.65% of adults.
• This translates to over 63,000 cases not captured by survey data alone.
• More accurate prevalence data can help improve mental health resource allocation and policy planning.
• Further research is needed to understand gaps between estimated prevalence and treatment program utilization.