The Role of Parliaments in Restoring Public Finances

Annex A. Methodology for the OECD Index on Parliaments and Fiscal Responsibility

The OECD Index on Parliaments and Fiscal Responsibility is designed to assess the extent to which national legislatures are in alignment with OECD Best Practices for Parliaments in Budgeting, covering five core themes: fiscal responsibility, budget approval, budget implementation & audit, committee organisation, and analytical resources (see Annex B) (OECD, 2023[1]). Scores range from 0 to 5 where 0 indicates minimal alignment and 5 reflects full alignment with the OECD Best Practices. The methodology used to build the 2025 OECD Index on Parliaments and Fiscal Responsibility draws on the recommendations and steps identified in the Handbook on Constructing Composite Indicators: Methodology and User Guide (OECD/European Union/EC-JRC, 2008[2]).

Data for the Index was primarily collected through the 2025 OECD Survey on Parliamentary Budget Oversight, which gathered responses from all 38 OECD Member countries. The survey focused exclusively on central/federal parliaments, with most responses provided by parliamentary budget officials. Responses represent the country’s own assessment of current practices and procedures as of 1 February 2025. Data collection ceased in July 2025, and a data cleaning process took place from July to September 2025. The process checked for internal and external consistency in the survey responses. During the review process, countries were invited to clarify and verify any substantial changes from the data submitted, including potential inconsistencies. 

While the Index allows for cross-country comparison, it is neither context specific nor does it purport to measure the overall quality of parliamentary budget oversight in each country or how well a country’s selected approach to parliamentary budget oversight operates. Instead, it offers a descriptive snapshot of alignment with the OECD Best Practices for Parliaments in Budgeting, helping countries identify areas for potential improvement.

Structure and weights of the Index 

The Index is structured around the 17 best practices in the OECD Best Practices for Parliaments in Budgeting, grouped into five thematic pillars: fiscal responsibility, budget approval, budget implementation and audit, committee organisation, and analytical resources (OECD, 2023[1]). Each pillar contributes equally to the overall Index score, with a maximum score of 1 per pillar, resulting in a total possible score of 5 (see Figure A.1).

Within pillars, best practices were weighted based on their relative importance. Indicator weights were determined by two factors: (i) the number of indicators associated with each best practice, and (ii) the significance of each indicator in relation to the best practice. Country scores are calculated by summing the scores across all five pillars.

The structure, indicators and weightings that make up the index were selected by OECD experts based on their relevance to the overarching concept. They have been reviewed by country delegates to the Working Party of Parliamentary Budget Officials and Independent Fiscal Institutions.

Figure A.1. OECD Index on Parliaments and Fiscal Responsibility: Structure and weights

Source: OECD authors’ elaboration.

Coding the data 

Each of the answer options in the 2025 OECD Survey on Parliamentary Budget Oversight were translated into quantitative indicators, varying from 0 to 1, with the value of one representing the highest value of the indicator and the value of zero representing the lowest. Although all indicators respect the [0,1] range, the method for assigning values to responses for questions vary by the type and structure of the question, such that:

• Binary-type questions (yes/no) were coded as 1 for “yes” and 0 for “no”.

• Ordinal-type questions (multiple answer options) were assigned values based on significance (e.g., 0, 0.5, or 1).

• For multi-response options questions, multiple options could receive the maximum value of 1 if deemed equally important.

Additional responses beyond the maximum were not counted, ensuring the score per indicator did not exceed the maximum score 1.

Only measures under implementation as of 1 February 2025 were considered in the 2025 OECD Index on Parliaments and Fiscal Responsibility.

Weighting and aggregation

Each pillar was weighted equally, with a maximum value of 1. Country scores were calculated using a linear aggregation method: weighted indicator scores were first aggregated to produce a pillar score (ranging from 0 to 1), and the five pillar scores were then summed to generate an overall Index score (ranging from 0 to 5). A score of 0 would indicate low alignment with the OECD Best Practices. A score of 5, by contrast, would mean the highest level of alignment with OECD Best Practices for Parliaments in Budgeting.

Tables A.1 to A.5 present a more detailed breakdown of the structure and weight for each of the five pillars of the Index. It also shows how the 2025 OECD Survey on Parliamentary Budget Oversight questions were used across each pillar, including the scoring system and the maximum combined index score that could be achieved when weighted.

Fiscal responsibility

The Fiscal Responsibility pillar distributes weight across four best practices reflecting increasing levels of legislative engagement in fiscal strategy. The largest share, 50%, was assigned to approval of aggregate budget totals (Best Practice 4), reflecting its central role in anchoring fiscal discipline. A further 20% was allocated to structured pre-budget debate (Best Practice 3), capturing upstream engagement in fiscal planning. The remaining 30% was evenly split between review of the fiscal framework (Best Practice 1) and scrutiny of fiscal risks and long-term sustainability (Best Practice 2), each assigned 15%.

Within Best Practice 1, the score is split between the legislature’s formal role (two thirds) and public consultation at the stage of establishing or changing the fiscal framework (one third). Each of the remaining best practices is measured by a single indicator and therefore receives its full assigned weight.

Table A.1. Methodology for fiscal responsibility

Pillar	Best Practice (weight)	2025 OECD Survey on Parliamentary Budget Oversight (weight)	Answer options / Indicators (score)	Maximum combined index score (per best practice)1
Fiscal Responsibility	1. The legislature can review and approve the national fiscal framework or major changes to the framework (15%)	1. What is the typical role of the legislature regarding changes to the fiscal framework? (10%)	Maximum score: 1 a. The legislature debates and approves changes. (1) b. The legislature debates changes but does not approve them. (0.5) c. The legislature has no role. (0) d. Other, please describe 2	Index score: 0.15 for all 0.10 for question 1 0.05 for question 31
		31. Please indicate the stages in the budget process where public consultation or citizen engagement typically occurs: Establishing or changing overall fiscal framework  (5%)	Maximum score: 1 a. Yes (1) b. No (0)
	2. The legislature should examine long-term fiscal sustainability analysis to debate risks faced by society in an open and informed manner and report on them to the public. (15%)	5. Please indicate the role of the legislature in relation to the following budget reports. j. Report on fiscal risks (15%)	Maximum score: 1 a. Submitted to legislature for information only (0.3) b. Discussed or debated by legislature (1) c. Requires legislature approval (1) d. Not applicable (0)	Index score: 0.15
	3. The legislature should debate budgetary priorities and trade-offs in a structured manner to inform preparation of the executive’s budget proposal. (20%)	2. Does the legislature hold a pre-budget debate on budget priorities and trade-offs that allows for its views to inform the executive's budget proposal? (20%)	Maximum score: 1 a. Yes, the legislature holds a pre-budget debate, and the results of this debate are sent as a report to the executive. (1) b. Yes, the legislature holds a pre-budget debate but does not produce a report. (0.5) c. No, the legislature does not hold a pre-budget debate. (0) d. Other, please describe 2	Index score: 0.20
	4. To demonstrate a commitment to fiscal responsibility, the legislature should review and approve the budget’s totals, providing a strict frame for the subsequent debate on allocative choices and potential amendments in the annual budget proposal. (50%)	3. During annual budget approval, does the legislature vote on the budget's totals (aggregate and specific ceilings for expenditure areas) before debating allocations and amendments? (50%)	Maximum score: 1 a. Yes (1) b. No (0) c. Other, please describe 2	Index score: 0.50

1. Including weights for pillar.

2. If a country indicated a response under “Other,” additional data validation was performed, and a custom score was applied to ensure an equal treatment across answer categories and countries.

Budget approval

Three best practices relating to review processes, documentation and amendment powers (Best Practices 5–7) were each assigned 20% of the total pillar score, reflecting their equal importance in enabling effective scrutiny.

The remaining 40% was allocated to timely approval of the budget (Best Practice 8), reflecting its critical role in ensuring the proper functioning and credibility of the budget process.

For Best Practice 5, the score was further divided across two indicators:

• 75% was assigned to the timeliness of budget submission, reflecting the importance of providing sufficient time for scrutiny.

• 25% was assigned to the ability to require testimony, capturing access to information during the review process.

Table A.2. Methodology for budget approval

Pillar	Best Practice (weight)	2025 OECD Survey on Parliamentary Budget Oversight (weight)	Answer options / Indicators (score)	Maximum combined index score (per best practice)1
Budget Approval	5. The legislature should have the opportunity, time and resources to effectively review, debate, and approve the executive’s budget proposal (20%)	Number of months the budget proposal is submitted prior to the start of the fiscal year (Q1 from 2023 OECD SBO Survey on Budget Frameworks)2 (15%)	Maximum score: 1 0 or less (0) 0 to 3 (# of months/3) 3 or more (1)	Index score: 0.20 for all 0.15 for question 1 0.05 for question 6
		6. The legislature and its committees can require the following groups to testify: (5%)	Maximum score: 1 a. Ministers/political appointees (0.4) b. Other officials from the executive (0.4) c. Persons not employed by government and/or key stakeholders (0.2) d. No ability to require testimony (0)
	6. The budget documentation submitted to the legislature should be comprehensive, encompassing all government revenue and expenditure, to facilitate realistic debate (20%)	7. The budget documents presented to the legislature include (20%)	Maximum score: 1 d. Comprehensive annual financial plan encompassing all revenues and expenditures, including off budget expenditures and extra budgetary funds (1) e. Comprehensive annual financial plan encompassing all revenues and expenditures, excluding off budget expenditures and extra budgetary funds (0.5)	Index score: 0.20
	7. The legislature should be empowered to make amendments to the executive’s budget proposal (20%)	8. What are the formal powers of the legislature to amend the budget? (20%)	Maximum score: 1 a. The legislature has unrestricted powers to amend the budget. (0.75) b. The legislature may make amendments but only if it does not change the total deficit/surplus proposed by the executive. (1) c. The legislature may only decrease existing expenditures/revenues (i.e. the legislature cannot increase existing items nor create new ones). (0.5) d. The legislature may not make any changes; it can only approve or reject the budget as a whole. (0) e. Other, please describe3	Index score: 0.20
	8. The annual budget should be approved prior to the start of the new fiscal year (40%)	Countries with legislature approval before the start of the fiscal year (Q1 from 2023 SBO survey)2 (40%)	Maximum score: 1 a. Yes (1) b. No (0)	Index score: 0.40

1. Including weights for pillar.

2. Data was pulled from the 2023 OECD Senior Budget Officials Survey on Budget Frameworks. In the case that a country didn’t participate in a survey, responses were filled in via desk research and by confirming with the country contacts when possible, such as in the case for Israel, Lithuania and Mexico.

3. If a country indicated a response under “Other,” additional data validation was performed, and a custom score was applied to ensure an equal treatment across answer categories and countries.

Budget implementation & audit

The weighting for this pillar was evenly distributed across the three best practices, reflecting their equal importance. Where multiple indicators were used for a given best practice, the weight was divided equally among those indicators.

Table A.3. Methodology for budget implementation & audit

Pillar	Best Practice (weight)	2025 OECD Survey on Parliamentary Budget Oversight	Answer options / Indicators (score)	Maximum combined index score (per variable)1
Budget Implementation & Audit	11. Any significant in-year changes to approved expenditure and their justifications, whether reallocation of funds, or an increase or a reduction in spending, should be put before the legislature and its relevant committees in the form of a supplementary budget for review and prior approval (33%)	19. Are supplementary budgets put before the legislature for review and prior approval? If (b) or (c) is selected for Q19 20: Are the thresholds for executive flexibility in spending and the main reasons for adopting supplementary budgets clearly specified in legislation? 2 (33%)	Maximum score: 1 a. Yes, always (1) b. Yes, mostly (0.5) c. Yes, sometimes (0.25) d. No, never (0) e. Other, please describe 3 f. Yes, mostly, and the thresholds for executive flexibility in spending and the main reasons for adopting supplementary budgets clearly specified in legislation (0.66) g. Yes, sometimes, and the thresholds for executive flexibility in spending and the main reasons for adopting supplementary budgets clearly specified in legislation (0.41)	Index score: 0.33
	12. Parliament should have the power to examine any interim financial reports that it deems necessary throughout the year (33%)	5. Please indicate the role of the legislature in relation to the following budget reports. f. Mid-year implementation report (33%)	Maximum score: 1 a. Submitted to legislature for information only (0.5) b. Discussed or debated by legislature (1) c. Requires legislature approval (1) d. Not applicable (0)	Index score: 0.33
	13. Parliament should effectively review the Audit reports prepared by the Supreme Audit Institution (33%)	24. Does the legislature have an Audit or Public Accounts Committee that examines the reports produced by the Supreme Audit Institution? (11%)	Maximum score: 1 a. No (0) b. Yes (1)	Index score: 0.33 0.11 for each indicator score (1)
		24.1. Is there a formal process for integrating the recommendations of the Audit or Public Accounts Committee into the upcoming budget approval process? (11%)	Maximum score: 1 a. No (0) b. Yes (1)
		25. Is there a plenary debate on the government’s year-end financial report? (11%)	Maximum score: 1 a. No (0) b. Yes (1)

1. Including weights for pillar.

2. In the Survey, question 19 & 20 were asked as two separate questions. For simplification in this index, answers to both questions were combined to make two new categories, (f) and (g), to allow for a greater range of scoring options.

3. If a country indicated a response under “Other,” additional data validation was performed, and a custom score was applied to ensure an equal treatment across answer categories and countries.

Committee organisation

The weighting for this pillar was constructed in a hierarchical manner based on expert judgement regarding the relative importance of its components.

First, 10% of the total pillar score was allocated to best practice on citizen engagement (Best Practice 16), reflecting its more limited but still relevant role within overall committee organisation.

The remaining 90% of the pillar score was then distributed between the two core institutional elements:

• 20% was assigned to sectoral committees (Best Practice 10), corresponding to 18% for the overall pillar;

• 80% was assigned to budget committees (Best Practice 9), corresponding to 72% for the overall pillar.

This weighting reflects the central co-ordinating role of budget committees in parliamentary budget oversight.

For Best Practice 9 (budget committees), the score was further divided across two survey indicators:

• Question 14 was given a weight of 87.5%, as it captures the most critical aspects of budget committee functioning, corresponding to 63.0% for the overall pillar score;

• Question 17 was assigned the remaining 12.5%, reflecting a more complementary role, corresponding to 9.0% for the overall pillar score.

Table A.4. Methodology for committee organisation

Pillar	Best Practice (weight)	2025 OECD Survey on Parliamentary Budget Oversight	Answer options / Indicators (score)	Maximum combined index score (per variable)1
Committee Organisation	9. The legislature should maintain a Budget committee with overall responsibility for budget scrutiny. (72%)	17. The Budget/Finance Committee in the unicameral/lower house have the right to: (9%)	Maximum score: 1 a. Consult outside experts (0.5) b. Employ outside experts (1) c. None of the above (0)	Index score: 0.09
		14. Which process best describes committees' role in the budget approval process in the unicameral or lower chamber? (63%)	Maximum score: 1 a. A single Budget/Finance Committee co-ordinates a process in which sectoral committees make recommendations to the Budget committee. The Budget committee then reviews and accepts or rejects these recommendations and formally considers all budget-related matters. (1) b. A single Budget/Finance Committee formally considers the budget, but members of sectoral committees attend meetings of the Budget committee to provide their view when spending in their specific areas is discussed. (0.75) c. A single Budget/Finance Committee formally considers budget aggregates (total level of revenue and spending and their allocation to each sector) and sectoral committees formally consider spending in their specific areas within ceilings set by the Budget/Finance committee. (1) d. A single Budget/Finance Committee formally considers budget aggregates (total level of revenue and spending and their allocation to each sector) and sectoral committees formally consider spending in their specific areas without ceilings set by the Budget/Finance committee. (0.5) e. There is no Budget/Finance Committee. Sectoral committees formally consider spending in their specific areas. (0) f. No formal committee involvement, but committees may choose to consider aspects of the budget. (0) g. The Budget committee formally considers the budget in every aspect. Sectoral committees have no role in the budget process. (0.5) h. Other, please describe2	Index score: 0.63
	10. Sectoral committees should review relevant portions of the budget in their portfolios and make recommendations to the Budget committee (18%)	15. Which committee(s) review(s) performance information attached to the budget in the unicameral/lower house? (18%)	Maximum score: 1 a. The Budget/Finance Committee (0.5) b. A subcommittee of the Budget/Finance Committee (0.5) c. Sectoral committees (1) d. No committee reviews performance information attached to the budget (0) e. Not applicable as no performance information is attached to the budget (0) f. Other, please describe2	Index score: 0.18
	16. The legislature and its committees should inform civil society and citizens on the budgetary debate and provide opportunities for them to contribute in a meaningful way. (10%)	30. Are legislative committee meetings typically open to the public and/or broadcast through audio, television or online channels? (2%)	Maximum score: 1 a. Legislative committee meetings are usually open to the public (1) b. Legislative committee meetings are sometimes open to the public (0.5) c. Legislative committee meetings are never open to the public (0) d. Other2	Index score: 0.10 0.02 for each indicator score (1)
		31. Please indicate the stages in the budget process where public consultation or citizen engagement typically occurs (2%)	Maximum score: 1 b. Medium-term budgeting (0.25) c. Annual priority setting and budget preparation (0.5) d. Budget approval (once laid at legislature) (0.25) e. Supplementary budgets (0.25) f. Consolidated government annual report and/or financial audit by the SAI (0.25) g. Public consultation or citizen engagement is not done (0)
		32. Please indicate the methods of public consultation or citizen engagement typically used during the budget process (2%)	Maximum score: 1 a. Public call for proposals and/or submissions Engagement led by the Budget/Finance Committee (0.5) b. Online consultation or questionnaire (0.5) c. Meetings, workshops or seminars open to all (0.5) d. Meetings, workshops or seminars with key stakeholders (0.5) e. Focus group(s) (0.5) f. Citizen’s panel(s) or assembly (0.5)
		37. Does the legislature engage in any of the following activities or initiatives to promote fiscal literacy and enhance citizen engagement? (2%)	Maximum score: 1 a. Organise outreach events with citizens (0.33) b. Organise education events with schools (0.33) c. Produce citizen's guide or explainers related to the budget (0.33) d. Other, please describe2
		36. How is citizen input received during the budget process typically handled? (2%)	Maximum score: 1 a. All input is published (0.5) b. A summary of the input is published (0.25) c. Minutes of meetings are published (0.25) d. Individual responses are provided to contributors, detailing how their input has been used in decision making/deliberation (1) e. The Budget/Finance committee incorporates input into decision making/deliberations, and there is a public record of this (1)

1. Including weights for pillar.

2. If a country indicated a response under “Other,” additional data validation was performed, and a custom score was applied to ensure an equal treatment across answer categories and countries.

Analytical resources

The Analytical Resources pillar assigns 80% of the total score to the availability of specialised analytical support and independent fiscal institutions (Best Practices 14 and 15), reflecting their central role in enabling effective scrutiny. The remaining 20% is allocated to the legislature’s control over its own budget (Best Practice 17).

Table A.5. Methodology for analytical resources

Pillar	Best Practice (weight)	2025 OECD Survey on Parliamentary Budget Oversight	Answer options / Indicators (score)	Maximum combined index score (per variable)1
Analytical Resources	14. The legislature should have specialist analytical support in the form of an in-house research or scrutiny unit or an independent parliamentary budget office to provide technical, expert and non-partisan analysis of fiscal policy and the budget. 15. The capacity of the legislature to engage in the budget process and broader fiscal policy debates is enhanced by the establishment of an independent fiscal institution (80%)	27. What specialised support is available to elected officials in relation to budget oversight? (answers a to f) IFI score (answer g.)3 (80%)	Maximum score: 1 a. In-house specialised budget unit (0.13) b. The research service has staff specialised in budget issues (0.05) c. The Budget/Finance Committee has staff specialised in budget issues (0.05) f. Other, please describe2 g. IFI (0-1)	Index score: 0.8
	17. The legislature alone should have the power to determine the budget of the legislature (20%)	39. Which option most accurately describes the way in which the budget for the legislature is prepared? (20%)	Maximum score: 1 a. The legislature prepares its budget and the central budget authority includes it in the executive's budget proposal without any changes. (1) b. The legislature is subject to the same procedures and policies as any other governmental organisation included in the executive's budget proposal. (0) c. The legislature prepares and votes on its budget directly. (1) d. Other, please describe2	Index score: 0.2

1. Including weights for pillar.

2. If a country indicated a response under “Other,” additional data validation was performed, and a custom score was applied to ensure an equal treatment across answer categories and countries.

3. For the IFI scores, data was sourced from the Fiscal Advocacy Index (OECD, 2025[3]). Specifically, country scores from the first two subdimensions – Independence and Analytical Focus – were combined and averaged to produce a final score ranging from 0 to 1. The primary data source for the Fiscal Advocacy Index is the 2021 IFI Database (OECD, 2021[4]).

Statistical analysis

Sensitivity testing

A useful test is to check the sensitivity of the index to different choices of weightings for each pillar included. We consider this using a run of 5 000 Monte Carlo simulations that assign random weights from a uniform distribution to each pillar. The results of the simulations are intended to show which institution would have been presented differently if the pillars were based on a different combination of weights.

Figure A.2 shows the results for the 2025 OECD Index on Parliaments and Fiscal Responsibility presented with a 90% confidence interval for each country. The upper bound of the interval is the 95th percentile of the simulation results and the lower bound is the 5th percentile of the simulation results. The size of the interval varies depending on each country’s data profile (mixed or rather even). Countries with an even answer profile (i.e. which gave similar answers for the majority of questions) will fall into a narrow interval, while countries with an uneven profile will fall into a broader interval (Freudenberg, 2003[5]). The results from the sensitivity analyses at pillar level show that, for the largest part of the countries analysed, total scores are not very sensitive to the choice of values given to the categories. The total scores of Australia, Belgium, Costa Rica, Estonia, Finland, Korea, the Netherlands, Switzerland and Türkiye appear to be more sensitive to the weightings applied, as shown by larger confidence intervals. It is important to note that not all the combinations of weights used to create these intervals can be viewed as realistic outcomes (Arndt et al., 2015[6]).

Figure A.2. 2025 OECD Index on Parliaments and Fiscal Responsibility: Sensitivity analysis at pillar level

Note: Figure presents the sensitivity of the index to various weighting assumptions (results from the Monte Carlo simulation where 5 000 different weights were assigned). Diamonds represent the indicator scores and vertical lines represent the 90% confidence intervals derived from the random weights analysis. Index comprised between 0 (low alignment) and 5 (high alignment).

Source: OECD analysis.

Statlink

One practical takeaway from this analysis is how reasonably institutions can be grouped together with a strong degree of confidence (Arndt et al., 2015[6]). The group of countries with black diamonds on the left-hand side of the graph not only have a total score for their composite indicator that is above the average (expressed as a horizontal dotted average line), but also have scores above the average for 90% of random combinations (this is the case for: Czechia, Italy, Greece, Lithuania, Mexico, Slovenia, the Slovak Republic, Spain, Sweden, and the United States). Conversely, on the right-hand side of the graph countries that are marked with black diamonds score below the average for 90% of random combinations (with Colombia and Costa Rica clearly well below the average). These two groups of countries can therefore be said to have index values which are significantly different from each other independent of the weighting scheme. 

Cronbach alpha testing

Cronbach’s Alpha is a measure often used to check the internal reliability of items in a model or survey, specifically that they are measuring the same underlying construct. It is based on the degree of correlation between a set of variables. A value equal to zero means that the variables are independent, while a value equal to one means that the variables are perfectly correlated. In general, a value of 0.7 or greater is an acceptable indication that the variables are measuring the same underlying construct. In terms of the overall Index, the estimated Cronbach’s Alpha is 0.70. This indicates that it is measuring a consistent underlying construct.

Correlation analysis

The table below presents the correlations between the overall index score and each individual pillar score (Table A.6). These correlations vary considerably, ranging from 0.40 to 0.72. Among the five pillars, fiscal responsibility and committee organisation show the strongest correlation with the overall index, while budget approval, budget implementation & audit, and analytical resources display relatively weaker correlations. While these latter pillars may not constitute internally coherent sub-measures from a purely statistical perspective, they were deliberately included to reflect the diverse yet complementary dimensions of parliamentary budget oversight. Their conceptual relevance remains strong, as they represent distinct aspects of the parliamentary budget oversight process rather than overlapping constructs.

Table A.6. Correlations between pillars and overall Index score

Pillar	Fiscal Responsibility	Budget Approval	Budget Implementation & Audit	Committee Organisation	Analytical Resources
Correlation with overall Index score	0.72	0.41	0.46	0.70	0.40

Although one might expect high correlations when measuring components of a shared concept, it is important to recognise that correlation values do not necessarily indicate the actual influence of individual indicators on the phenomenon being assessed (OECD/European Union/EC-JRC, 2008[2]).

Limitations of composite indexes

Composite indexes are useful to summarise large amounts of discrete, qualitative information. As Nardo et al. note, they are “much easier to interpret than trying to find a common trend in many separate indicators” (Nardo M, 2005[7]). However, composite indexes have their limitations. They are easily and often misinterpreted by users due to a lack of transparency as to how they are generated. This can present difficulties in terms of unpacking an index and understanding what it is actually measuring.

The 2025 OECD Index on Parliaments and Fiscal Responsibility, while providing cross-country comparison, should not be seen as a measure of quality or as a ranking. It is not context specific, nor can fully capture the complex realities of the quality or effectiveness of parliamentary budget oversight. It shows that countries have adopted multi-initiative approaches to parliamentary budget oversight by using each of the five pillars. It should also be noted that countries with the same or similar index scores may have very different profiles (e.g. more balanced scores or an uneven score across pillars). Examining the results at the pillar level is therefore crucial to identify areas for further improvement.

Composite indexes should be seen as a means of initiating discussion and stimulating public interest (OECD/European Union/EC-JRC, 2008[2]). To help with interpreting the findings and to provide a more detailed analysis of the strengths and weaknesses of budget oversight by parliaments, the results of the 2025 OECD Index on Parliaments and Fiscal Responsibility should be complemented with in-depth country assessments. These country assessments provide a more detailed analysis of the quality of country practices in the context of diverse and country-specific governance structures, administrative cultures, institutional set-ups and priorities.

References

[6] Arndt, C. et al. (2015), “2015 Indicators of Regulatory Policy and Governance: Design, Methodology and Key Results”, OECD Regulatory Policy Working Papers, No. 1, OECD Publishing, Paris, https://doi.org/10.1787/5jrnwqm3zp43-en.

[5] Freudenberg, M. (2003), “Composite Indicators of Country Performance: A Critical Assessment”, OECD Science, Technology and Industry Working Papers, No. 2003/16, OECD Publishing, Paris, https://doi.org/10.1787/405566708255.

[7] Nardo M, S. (2005), Tools for Composite Indicators Building, European Commission, https://publications.jrc.ec.europa.eu/repository/handle/JRC31473.

[3] OECD (2025), Government at a Glance 2025, OECD Publishing, Paris, https://doi.org/10.1787/0efd0bcd-en.

[1] OECD (2023), “OECD Best Practices for Parliaments in Budgeting”, OECD Journal on Budgeting, https://doi.org/10.1787/33109e15-en.

[4] OECD (2021), Independent Fiscal Institutions Database, OECD, Paris, https://webfs.oecd.org/governmentataglance/Budgeting/IFI%20Independent%20Fiscal%20Institutions%20Database.zip.

[2] OECD/European Union/EC-JRC (2008), Handbook on Constructing Composite Indicators: Methodology and User Guide, OECD Publishing, Paris, https://doi.org/10.1787/9789264043466-en.